WO2000038360A1

WO2000038360A1 - Television audience monitoring system and method detecting light emitted by a display of a cable converter box

Info

Publication number: WO2000038360A1
Application number: PCT/US1999/028429
Authority: WO
Inventors: Lester L. Jarrell
Original assignee: Adcom Information Services, Inc.
Priority date: 1998-12-21
Filing date: 1999-12-01
Publication date: 2000-06-29

Abstract

An optical interface device and method for determining a currently tuned-to channel of a set-top converter box having an electronic display that indicates the currently tuned-to channel via seven-segment elements. The optical interface device includes a plurality of phototransistors, each of which are optically coupled to individual segments of the seven-segment elements. The device further includes a controller that receives signals from said phototransistors and generates information representative of the currently tuned-to tuned channel for use by downstream components. The information representative of the tuned channel may be output as an ASCII value representative of the currently tuned-to channel. The optical interface may be part of a viewership metering system when used in conjunction with a viewership collection meter to determine viewer habits.

Description

TELEVISION AUDIENCE MONITORING SYSTEM AND METHOD DETECTING LIGHT EMITTED BY A DISPLAY OF A CABLE CONVERTER BOX

FIELD OF THE INVENTION

The present invention relates to a device for monitoring usage of audiovisual equipment. In particular, the present invention relates to a device for interfacing with set-top converter boxes in a non-invasive manner in order to determine a channel being watched by a television viewer.

BACKGROUND OF THE INVENTION

Determining a number of viewers watching a particular television program is of great importance to television networks, stations, programmers and advertisers.

Information regarding the number of viewers is used to determine market share and the ratings of particularprograms. This information is additionally used to determine advertising rates, which in turn affects the revenue generated by the television networks and stations.

There are numerous systems known in the art that attempt to monitor the viewing habit of television watchers. Early attempts at monitoring were fairly simple and unsophisticated, and generally required viewers to maintain a diary of programs watched. As the viewers began and finished watching a particular channel or program, they entered a start and end time in to the diary. The viewers periodically mailed the diaries to a central collection location, which then processed the diaries. The disadvantages of such a system are many, including: failure to enter information into the diaries, inaccurate entries into the diaries, and delays in processing. Further, as the number of channels provided to households has increased dramatically, it has become increasingly difficult for viewers to accurately track their viewing habits

Later attempts have become more sophisticated and efficient by automating portions of the data collection process and the determination of the channel currently being viewed For example, U S Patent No 4,642,685, to Roberts et al , discloses a television monitoring system having a channel detection unit, a people monitoring unit, a transmission unit, and a receiving unit The channel detection unit detects ultra or very high frequency radiation emitted from a television tuner to determine if the channel being tuned is one of the channels which have been preset into the detection unit The detection is performed by a pick-up probe that inductively couples the signal emitted from the local oscillator of the television receiver The people monitor unit is a powered handset that includes buttons assigned to each of the individuals who will be viewing the television set The viewer depresses his or her assigned button to indicate he or she has started to watch the television The viewing data is stored and transmitted by the transmission unit over household wiring to the receiving unit The receiving unit sends the collected information to a central computer via a telephone connection While this system speeds the data transmission process to the central computer as compared to mailing diaries to a processing center, there are several disadvantages in this system For example, those of skill in the art will recognize that the location of the pick-up probe will greatly affect the sensitivity and accuracy of the channel detection unit Further, as each viewer must manually depress a button on the people monitor, it is subject to the same inaccuracies of the diary method noted above, I e , the failure of viewers to record the television channels actually watched

U S Patent No 4,907,079, to Tuner et al , describes networked conventional audio and visual equipment that communicate via telephone lines with a remote central computer The viewer provides channel selection commands or other programming commands to a microprocessor through an infrared remote control A VCR tuner and TV tuner within the system provide audio and video signals for the conventional television monitor or television receiver An AM and FM radio tuner may also be included, tunable by the microprocessor In the Tuner et al system, the video and/or audio signals from each tuner, video tape player, and disc players are coupled to the input side of an audio switch and a video switch The switches are microprocessor controlled so that the audio and video program - j - from any source may be coupled to any output or display device at the viewing location. The system includes a motion detector to determine the presence of viewers and provides for communication with a remote computer to monitor use of each networked audiovisual unit. While this system provides for monitoring and logging of each networked audiovisual unit, the Tuner et al. system is designed to control a large home-entertainment system, rather than a small-scale solution to monitoring viewers' habits. In particular, the Turner et al. system is indicated to cost a few hundred dollars, and would fail to provide a solution to television networks and advertisers who are interested in obtaining accurate viewing statistics by deploying systems to a relatively large number of viewers. U.S. Patent No. 4,912,552, to Allison, III, et al., describes a system that collects television channel tuning data that transmits the data to a central site in a transparent manner to the occupants of the household. The system is designed having a hub and spoke architecture, where the hub unit communicates with metering devices attached to television receivers and/or cable television converters. The meters are periodically polled by the hub, which then collects the data acquired by each meter. The hub communicates with a host computer via standard telephone lines. The Allison, III, et al. system particularly describes the central hub device and gathering data before transmitting it to the central site. However, the Allison, III et al. system fails to provide an improved metering unit by contemplating the use of known channel meters. U.S. Patent No. 5,374,951, to Welsh, discloses a system for monitoring and recording data related to television program viewing habits that includes a plurality of remote program monitor units that automatically report such data to a central computer via a conventional telephone network. The monitor unit reads a character string that is decoded from the demodulated television signal received by the unit. The character string is compared to a string table stored within the unit to determine the content being viewed by the television watcher. If there is a match, an event code and a time are stored in the unit for reporting to the central computer. However, for the system to operate, the character string must be encoded into the received television signal, otherwise there will be no match with the string table stored in memory. Further, the string table must be kept current for the system to provide accurate results. U.S. Patent No. 5,382,970, to Kiefl, describes a system for monitoring and collecting data on the viewing habits of television viewers that includes a portable personal data collection device that is separate from the television or set-top converter. The personal data collection devices includes a detector for providing a station identifier identifying the particular broadcast signal being received by the receiver, a clock for providing a signal representing time, a memory for storing data, and a cellular telephone module for communicating with a central location. The cellular telephone module periodically transmits stored data within the device to the central location. The viewer may enter channel information directly into the device, or the device may include a detector for detecting a channel selection signal from a television remote control to change the station identifier stored in memory. While this is an improvement over diaries, this system requires a personal data collection device for each individual watching a particular television set. Further, because the device is physically separate from the television set, the data collected may not be accurate as viewers may either fail to enter channel information or the device may not detect an infrared transmission from the television remote control.

U.S. Patent No. 5,495,282, to Mostafa, et al., discloses a tuning/monitoring module for monitoring use of a video equipment without the use of probes by injecting RF signals into a cable converter and a NCR in order to detect channels selected by the cable converter and the NCR. In accordance with signals received from the cable converter and the NCR, the tuning/monitoring module can determine a selected channel being viewed by the viewers. Channel identification signals are also injected into the NCR and cable converter for recording by the NCR on videotape. The state of the "TV/NCR" switch of the NCR is determined by injecting a code signal into the VCR and determining whether that signal is present in an RF video signal output by the NCR. The receiver also receives data contained in channel identification signals. The receiver is selectively connectable to the NCR and the cable converter. However, this system requires the use of the special tuning/monitoring module in place of a tuner provided with a television or VCR in order to provided the injected signal to determine the viewed channel. Such a special tuning/monitoring module increases the expense associated with tracking viewers' habits. In view of the above, there is a need for an integrated solution to detect the channels being watched by viewers There is also a need for a system that does not interfere with any of the consumer's electronics, equipment or features In particular, there is a need for a system that provides channel information without requiring addition steps to be taken by viewers, and that functions such that the consumer's VCR, TV, remote controls are not tampered with or opened and continue to operate normally

SUMMARY OF THE INVENTION

In view of the above, the present invention, through one ormore of its various aspects and/or embodiments is thus presented to accomplish one or more objects and advantages, such as those noted below According to an aspect of the present invention, there is provided an optical interface device for use in determining a currently tuned-to channel of a set-top converter box having an electronic display The optical interface device includes a plurality of light receiving elements that are adapted to receive light emitted by the electronic display, and a controller that is connected to the light receiving elements and which receives signals from the light receiving elements indicative of whether the light receiving elements are receiving light from the electronic display The controller scans the electronic display and receives the signals to generate information representative of the currently tuned-to tuned channel

According to a feature of the present invention, the electronic display includes a plurality of seven-segment elements that are each adapted to display an alphanumeric character that includes the currently tuned-to channel of the set-top converter box, and the light receiving elements are arranged in a pattern that corresponds to segments of the seven- segment elements Each of the light receiving elements is arranged to receive light from one segment of each seven-segment display element

According to a further feature of the invention, the controller scans each of the plurality of seven-segment elements at a predetermined frequency The signals from the light receiving elements are input to predetermined pins of an input/output port of the controller in order to determine the alphanumeric character, and upon scanning each of the seven- segment elements of the electronic display, the controller determines the information representative of the currently tuned-to tuned channel According to another feature, the information representative of the tuned channel includes an ASCII value representative of the currently tuned-to channel, and the controller outputs the ASCII value to a viewership meter connected to the optical interface via an electrical connection According to yet another feature, the viewership meter includes an audio matching circuit that compares a first audio signal of a predetermined channel tuned by the viewership collection meter with a second audio signal output by a television to which the set- top converter is connected If the first audio signal and the second audio signal match, the viewership collection meter determines that the channel to which the set-top converter box is tuned is the predetermined channel

According to a feature of the invention, the light receiving elements comprise phototransistors and the electronic display includes seven-segment elements, the phototransistors are turned ON and OFF in response to receiving incident light from the seven-segment elements, and the signals comprise one of a logic high and a logic low state According to a further feature of the invention, the optical interface device is adapted to be mounted to the electronic display such that each of the phototransistors are arranged to receive light from one segment of each seven-segment display element The seven-segment elements comprise LED display elements

According to another feature of the invention, the optical interface device is adapted to receive power and additional data via the second electrical connection

According to another aspect of the invention, there is provided a system for determining viewership of channels tunable by a set-top converter box having an electronic display The system includes an optical interface device which receives light emitted from the electronic display and a viewership collection meter connected to the optical interface device, the viewership meter periodically storing a channel to which the set-top converter is tuned The channel to which the set-top converter is tuned is determined by the optical interface device and communicated to the viewership collection meter, and the viewership collection meter stores the channel and forwards it to a predetermined location at selected times

According to afeatureofthe invention, the viewership collection meter further includes an audio matching circuit that compares a first audio signal of a predetermined channel tuned by the viewership collection meter with a second audio signal output by a television to which the set-top converter is connected If the first audio signal and the second audio signal match, the viewership collection meter determines that the channel to which the set-top converter box is tuned is the predetermined channel

According to a further feature, the optical interface device includes phototransistors and the electronic display includes seven-segment elements The phototransistors are turned ON and OFF in response to incident light from the seven-segment elements, and the phototransistors output signals that comprise one of a logic high and a logic low state to indicate the presence or absence of incident light

According to yet another feature, the optical interface device is adapted to be mounted to the electronic display such that each of the phototransistors are arranged to receive light from one segment of each seven-segment display element The seven-segment elements may comprise LED display elements

According to yet another aspect of the present invention, a method of determining a channel to which a set-top converter box is tuned using a optical interface is provided, where the set-top converter includes an electronic display that is driven by drive signals The method includes receiving light for the electronic display at the optical interface, outputting signals from the optical interface representative of received light, determining a channel to which the set-top converter box is tuned by sampling the signals, generating a coded representation of the determined channel, and outputting the coded representation

According to a feature of the invention, the electronic display includes at least one seven-segment display element, the step of determining a channel to which the set-top converter box is tuned further includes (a) determining which segments of the seven-segment display element is illuminated, (b) determining a character being displayed by the seven- segment display element, and (c) repeating steps (a) and (b) for each seven-segment display element in the electronic display

According to another feature of the present invention, the step of generating a coded representation of the determined channel includes generating an ASCII value of the channel to which the set-top converter box is tuned Also, the step of outputting the coded representation may comprise serially transmitting the ASCII value to a viewership meter According to yet another feature, the method further includes storing, at the viewership meter, the ASCII value and forwarding the ASCII value at predetermined times to a central collection site

Other features of the invention are described below

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing summary, as well as the following detailed description of the preferred embodiments, is better understood when read in conjunction with the appended drawings For the purpose of illustrating the invention, there is shown in the drawings an embodiment that is presently preferred, in which like references numerals represent similar parts throughout the several views of the drawings, it being understood, however, that the invention is not limited to the specific methods and instrumentalities disclosed In the drawings

Figure 1 is an overview of the environment in which the television audience monitoring system of the present invention may be implemented, Figure 2 is a block diagram illustrating an optical interface device in accordance with the present invention coupled to a television set-top converter box,

Figure 3 is a schematic diagram illustrating the optical interface device of the present invention in greater detail,

Figure 4 is a block diagram of an exemplary collection meter in accordance with an aspect of the present invention, and

Figure 5 is an exemplary flow chart illustrating the steps and processes performed by a microcontroller provided with the optical interface device

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention provides a method and apparatus for detecting the currently tuned-to channel of a subscriber's set-top converter box hav gan electronic display that indicates the channel and status The information related to the detected channel may then be forwarded to a data collection system within the subscriber's home or other location for eventual transmission to a central data collection and compilation site Such information, taken from a large sample size, may be used to measure network viewing and the interactive environment

In order to obtain accurate viewership data, it is preferable to gather data from a large sample of subscriber homes within a cable satellite system's broadcast base The sample is typically derived from demographic and lifestyle characteristics, shopping patterns, and consumer profile of the subscribers' homes Ideally, the sample of homes from the entire system should represent the system as a whole To collect data, each of the homes to be sampled may be supplied with a viewership meter (described below) The viewership meter is preferably supplied by ADcom Information Services, Ine , Carlsbad, California, and is installed on each television in the sampled homes Such a meter is quickly and easily installed as compared to other known meters and provides a complete record of viewing in each participating household When the quantitative ratings from the viewership meters are complied, the information may beused by advertisers and network programmers to accurately target audiences and determine ideal spot placement for advertisements Referring to Figure 1, there is illustrated an overview of an exemplary environment within which the present invention may be embodied As illustrated, signals from a satellite/cable system provider are received via transmission lines 11 connected to one of a satellite dish 13 or power poles 15 The satellite dish 13 may receive signals from a plurality of earth orbiting satellites (not shown), whereas the transmission lines 11 strung over power poles 15 (or buried underground) may be connected to a transmission site (not shown) The transmission lines 11 enter the viewer's home or other location and are typically connected to a wall plate 12 having a 75Ω co-axial connector

To provide a signal to a viewer's television set 10, a first 75Ω co-axial cable 14 electrically connects the transmission line 11 , at the wall plate 12, to a first connection on, e g , the rear panel of a set-top converter box 16 A second 75Ω co-axial cable 14 connects between a second connection on the rear panel of the set-top converter 16 and to, e g , a 75Ω connector in a television set 10 The set-top converter box 16 is used to selectively tune channels in accordance with a viewer selection Alternatively, a single 75Ω co-axial cable 14 may be used to provide signals directly to the television set 10 Also as shown, the television set includes an audio-out jack 10a The set-top converter 16 is connected to a viewership collection meter 18 by wires or a cable 24 Alternatively, an electrical connector or the like may be used in place of wires or cabling 24 to connect the viewership meter 18 and the set-top converter 16 The viewership meter 18 is designed such that it may connect to any television 10 or set-top converter 16 In accordance with an aspect of the present invention, the collection meter 18 determines a viewed channel by receiving channel-related information from an optical interface device 22 (described below with regard to Figures 2 and 3) The collection meter 18 may also use an audio matching technique to log channel viewership throughout the day The collection meter 18 is preferably capable of recording the channel location (I e , the tuned channel) every five seconds, storing the information and forwarding it to a central computer (not shown) The data is forwarded by telephone or other means during time periods when the transmission to the central site is unlikely to interfere with the occupants' use of the transmission media The central computer collects the data from all viewership meters 18, analyzes the information, combines the records with additional qualitative data, and sends prepared reports to the system operator as early as the next day Preferably, hundreds, or even thousands of viewership meters 18 may be managed from one central system Data and reports are received by the system operators via e g , the Internet and Frame Relay routers System personnel can quickly generate custom reports that show channel ratings by day, target and network ranking Referring now to Figures 2 and 3, there is illustrated the optical interface device 22 of the present invention Set-top converter boxes 16 typically include seven- segmentLED display elements (l e , elements 23a-23c) to indicate alphanumeric information (e g , a channel) to a television viewer The present invention is directed to an apparatus for optically monitoring such seven-segment elements and for determining the channel number (or letter) displayed by the set top converter box 16 In particular, Figure 2 illustrates an exemplary configuration of the optical interface device 22 of the present invention, where the optical interface device 22 is positioned over, or proximate to, the display 16a to receive light emitted from each of the seven-segment elements 23 a-c The optical interface device 22 may be fastened to the set-top converter box 16 by an adhesive glue, tape, a snap fitting, or other means to be properly positioned with respect to the seven-segment elements 23 It is noted that other configurations, such as mounting the optical interface device 22 within the set-top converter box 16 are within the scope of the present invention

Referring now to Figure 3, there is illustrated an exemplary schematic of the optical interface device 22 As illustrated, the exemplary optical interface device 22 includes a microcontroller U7, a connector J4, and a plurality of phototransistors Q3-Q23 which receive a biasing voltage from a voltage source VCC via a resistor network comprising resistors R2-R7 The microcontroller U7 is preferably an 8-bit microcontroller having a Reduced Instruction Set Computer (RISC) architecture and includes dedicated digital input lines, digital output lines, and an on-board programmable memory The microcontroller U7 may also provide capabilities such as a real-time clock and a modem chip-set Preferably, the microcontroller U7 comprises aAT90S1200, manufactured by Atmel Corporation, San Jose, California Other similar microcontrollers may beused, as the present invention is not limited to the above-noted microcontroller As will be discussed in greater detail below, the microcontroller U7 receives voltages (via the input/output ports) over input lines 25 that are representative of the channel displayed by the set-top converter box 16 The voltages are converted by the microcontroller U7 into channel data, which is temporarily stored in an internal random access memory (RAM) or other memory, and transmitted to the collection meter 18 over a line 20 (Figure 4) connected to connector J4

The optical interface device 22 preferably comprises a printed circuit board, such that the phototransistors Q3-Q23 may be located in close proximity to respective segments of the seven-segment elements 23a-c when the optical interface device 22 is mounted to the display 16a As illustrated in Figure 3, the phototransistors Q3-Q23 are arranged on the printed circuit board in a pattern that corresponds to the seven-segment elements 23a-c The phototransistors Q3-Q23 are preferably positioned to maximize the viewing area of their respective segments and minimize the interference with each other Preferably, the printed circuit board defines cut-out regions such that the seven-segment elements 23a-c are visible to the television viewer when the optical interface device is mounted thereto Alternatively, the printed circuit board may be fabricated from an optically clear material The operation of the optical interface device 22 will now be described When the segments of the seven-segment elements 23a-c of the display 16a are illuminated to indicate a channel to which the set-top converter box 16 is tuned, corresponding ones of the phototransistors Q3-Q23 receive light emitted from the illuminated segments and are turned ON. As shown in Figure 3, the emitter of each of the phototransistors Q3-Q23 is connected to a lead that is connected to one of microcontroller port I/O port pins PB5-PB7. A voltage from voltage source VCC, as dropped by resistors R2-R7, is presented to the collector of each of phototransistors Q3-Q23 and pins PDO, PD1, PD2, PD3, PD4, PD5 and PB1 of the microcontroller U7 via lines 25. The voltage is utilized by the microcontroller U7 as a logic high value, as described below.

In order to determine which segments of each of the seven-segment elements 23a-c are illuminated, the controller U7 scans each of the seven-segment elements 23a-c at a predetermined frequency. This scanning is performed by pulling one of I/O port pins PB5- PB7 low to select the phototransistors that correspond to the seven-segment element 23 to be scanned. In the exemplary circuit, I/O port pin PB7 corresponds to the phototransistors that monitor segments of seven-segment element 23a; I/O port pin PB6 corresponds to the phototransistors that monitor segments of seven-segment element 23b; and I/O port pin PB5 corresponds to the phototransistors that monitor segments of seven-segment element 23 c.

If a segment of a seven-segment element 23a-c is illuminated, its corresponding phototransistor on the optical interface device 22 will be turned ON. When the seven-segment element 23 a, 23b or 23c is selected to be scanned (i.e., by pulling I/O port pin PB7, PB6 or PB5 low, respectively), a current path from VCC to the pulled-low pin PB5, PB6 or PB7 is completed. For those phototransistors receiving light (i.e., those phototransistors turned ON), the voltage presented to its corresponding pin of the I/O port pins (e.g., pins PDO, PD1, PD2, PD3, PD4, PD5 or PB 1) is at a logic low level, whereas, if the phototransistor is not receiving light (i.e., turned OFF) the voltage at the I/O port pin is at the logic high level.

By sampling the I/O ports when one of I/O port pins PB5-PB7 is low, the microcontroller U7 can determine which segments are illuminated for a particular seven- segment display element 23a, 23b or 23 c, and, accordingly, can determine the particular number (or letter) being displayed by that seven-segment display element 23a, 23b or 23c. After scanning all three segments, the channel number displayed by the set-top converter box 16 may be determined. The determined channel number may then be converted to, e.g., an ASCII value or other format, and output to the viewership collection meter 18 for further processing

Although three LED displays 23 are illustrated in the Figures, it is within the scope of the present invention to include fewer or more LED displays 23 or other displays capable of displaying alphanumeric information (e g , vacuum flourescent) Similarly, while the phototransistors Q3-Q23 are illustrated as arranged to couple with three display elements (e g , 23a-c), other numbers of seven-segment elements 23 may be coupled by the optical interface device 22 of the present invention, as necessary Additionally, data and power may be transferred between the optical interface device 22 and external devices over connector J4 Figure 4 is a block diagram of the exemplary components withm the collection meter 18 The collection meter 18 generates "snapshots" of selected channels on cable, satellite and standard air systems and compiles information related to the snapshots The information may include the channel or channels viewed at a particular time or on a particular day The complied information may be used to generate viewership ratings and other researchrelatedservicesformulti-channel subscπbertelevision systems (e g , cable television and satellite television)

The collection meter 18 includes Audio interface devices 32, a communications module 26, a digital signal processor (DSP) controller 27, a flash memory 28 to store parameters and programming information for the DSP controller 27, a CODEC 30 to provide for compression and decompression of data (e g , audio or video information) in accordance with predetermined mathematical algorithms, a real time clock 30, and a power supply and voltage supervisor 31 The DSP controller 27 may be programmed to provide functionalities such as, tuning to cable channel frequencies, detection of the state of the television (e g , powered ON or OFF), detection of the channel being viewed, communication to the communications module 26, management of storage of snapshot information (e g , tιme stamp), reception and storage of information related to a telephone number of a central collection site and time for sending snapshot information to the central site, dial-up capability to contact the central site and to upload the snapshot information, and a capability to receive time and reset the onboard real time clock during the upload Additional features and functionalities may be provided as user requirements change by reprogramming the DSP controller 27 As illustrated, the DSP controller 27 receives information over line 20 from the optical interface device 22 (from connection J4)

The dial-up capability is preferably programmed in firmware within the DSP controller 27 and is preferably not programmable by end-users (e g , viewers) To performed the dial-up function, the communications module 27, which is connected to the customer's telephone line, is taken off-hook in accordance with the V 22 protocol at predetermined times and dual-tone multi-frequency (DTMF) signals are transmitted to call the central collection site The telephone number of the central collection site is preferably coded into the firmware and may be changed by the central site during data communications Using the V 22 protocol, the communications module 27 transmits signals representative of the data collected by the collection meter 18 to the central site As illustrated in Figure 4, the communications module 27 may comprise a MODEM

The power supply 31 regulates the voltage to the communications module 27 and the Audio interface devices 32 The power supply 31 receives, for example, 12V AC and may provide, ±5V and ±12N DC to the modules 27 and 32 The voltage supervisor portion monitors the +5N and +12N and resets the DSP controller 26 and the flash memory 28 if the supplied voltage drops below these values The total power consumption is preferably less than 5 Watts

The audio interface devices 32 include an RF amplifier 33, a mixer 34, an FM demodulator 35, a low-pass filter 36, audio comparator 37, voltage controlled oscillator (NCO) 38, and a frequency synthesizer 39 The broad-band cable signal to the television set 10 enters through a coaxial cable 14 coupled to the Audio interface devices 32 The audio sub-carrier of a particular cable channel is coupled to the low pass filter 36 and the RF amplifier 33 by a low-loss coupler The signal is converted to a predetermined frequency (e g , 3 25 MHz) by the mixer 34, the local oscillator 38 and the frequency synthesizer 39, which is controlled by the DSP controller 27 The predetermined frequency is demodulated by the FM demodulator 35 so the audio program for a tuned channel may be recovered The audio signal from the television set 10 is obtained from an audio pick-up device (not shown) or from the audio jack 10a in the television set 10 The audio pick-up device is coupled to the television set 10 to detect the audio signal broadcast The audio signal is fed to the RF amplifier 33 and then into an audio comparator 37. The recovered audio from the FM demodulator 35 is also fed into the audio comparator 37 and compared with the television audio signal. If the audio frequencies match, then a logic high signal is sent by the audio comparator 37 to the DSP controller 27. If there is not a match between the recovered audio from the FM demodulator 35 and the television audio, then the DSP controller 27 tunes the frequency synthesizer 39 to the next channel and continues until a match is found.

The collection meter 18 may be enclosed in an assembly (not shown) that includes internal-metalized plastic covers. The Audio interface devices 32 may be mounted on the bottom cover and the communication module 27 mounted up-side-down on the top of the Audio interface devices 32. The optical interface devices 22 may be mounted on the top cover. The assembly may include the following interfaces: a 75Ω cable in (54 MHz to 1 GHz, -16dBmN to +10 dBmN), a power adapter in (12 VAC, <420mA), audio in (1 V„, 100 Hz to 5kHz, >lkΩ impedance), a magnetic sensor in (5mV_Pi„ 100 Hz to 5 kHz, lkΩ impedance), a POTS In/Out (RJ-11, meets FCC Part 68 requirements), and a power/mode indicator (green LED).

It is further noted that the schematics, components, and component values of Figures 3 and 4are provided herein for exemplary purposes only. Accordingly, the present invention is not limited to the specific structural relationships, components and component values disclosed as other structural relationships, components and component values are intended to be included within the scope of the present invention, as recited in the appended claims. For example, the collection meter 18 may include a microprocessor or microcontroller and associated circuitry to perform the various functions of the DSP controller 27. Further, additional or fewer communications interfaces may be provided (e.g., power line data communication, RF data communication, or digital telephony). Also, the set- top converter box 16 may be modified to include the components of the collection meter 18, such that a single set-top device performs the functions of both devices.

Figure 5 is a exemplary flowchart of the sequence of operations performed by the microcontroller U7 in accordance with an aspect of the invention. At step 100 the variables, data space and serial ports are initialized. At step 102, the microcontroller I/O ports are initialized and set. In the Atmel AT90S 1200, two I/O ports are provided (Port B and Port D) having 8 and 7-bit widths, respectively As noted in step 102 and illustrated in Figure 3, bits 5-7 of Port B are set to scan the LED display 23, and bit lof Port B and bits 0-5 of Port D are set to receive the segment lines of the LED display 23 Bit 0 of Port B and bit 6 of Port D are set to output serial data to connector J4 Steps 100 and 102 are typically executed at power-up or during a reset operation

At step 104, pm 7 of port B is pulled low such that segment data from character 1 (l e , the first LED display 23 a) may be received At step 106, the segment data for character 1 is captured and stored in memory in the microcontroller U7 At step 108, pm 6 of port B is pulled low such that segment data from character 2 (I e , the second LED display 23b) may be received At step 110, the segment data for character 2 is captured and stored in memory in the microcontroller U7 At step 1 12, pin 5 of port B is pulled low such that segment data from character 3 (l e , the third LED display 23 c) may be received At step 114, the segment data for character 3 is captured and stored in memory in the microcontroller U7 At step 116 the channel information captured at steps 106, 110 and 114 is converted into ASCII and serially transmitted to the collection meter 18 at a predetermined data rate After the transmission is complete at step 118, the process returns to step 104

As described above, the present invention provides for a novel apparatus and method for capturing information related to the channel to which a set-top converter box is tuned and for converting the information into data having a format compatible with a viewership data collection meter

It is noted that the foregoing examples have been provided merely for the purpose of explanation and are in no way to be construed as limiting of the present invention While the invention has been described with reference to preferred embodiments, it is understood that the words which have been used herein are words of description and illustration, rather than words of limitations Further, although the invention has been described herein with reference to particularmeans, materials and embodiments, the invention is not intended to be limited to the particulars disclosed herein, rather, the invention extends to all functionally equivalent structures, methods and uses, such as are within the scope of the appended claims Those skilled in the art, having the benefit of the teachings of this specification, may effect numerous modifications thereto and changes may be made without departing from the scope and spirit of the invention in its aspects.

Claims

WHAT IS CLAIMED IS:

1. An optical interface device for use in determining a currently tuned-to channel of a set-top converter box having an electronic display, said optical interface device comprising: a plurality of light receiving elements, said light receiving elements adapted to receive light emitted by said electronic display; a controller, said controller being connected to said light receiving elements and receiving signals from said light receiving elements indicative of whether said light receiving elements are receiving light from said electronic display, wherein said controller scans said electronic display and receives said signals to generate information representative of said currently tuned-to tuned channel.

2. The optical interface device as recited in claim 1, said electronic display comprising a plurality of seven-segment elements that are each adapted to display an alphanumeric character that comprises said currently tuned-to channel of said set-top converter box, wherein said light receiving elements are arranged in a pattern that corresponds to segments of said seven-segment elements, and wherein each of said light receiving elements is arranged to receive light from one segment of each seven-segment display element.

3. The optical interface device as recited in claim 2, wherein said controller scans each of said plurality of seven-segment elements at a predetermined frequency.

4. The optical interface device as recited in claim 3 , wherein said signals from said light receiving elements are input to predetermined pins of an input/output port of said controller in order to determine said alphanumeric character, and wherein upon scanning each of said seven-segment elements of said electronic display, said controller determines said information representative of said currently tuned-to tuned channel.

5 The optical interface device as recited in claim 4, wherein said information representative of said tuned channel comprises an ASCII value representative of said currently tuned-to channel, and wherein said controller outputs said ASCII value to a viewership meter connected to said optical interface via an electrical connection

6 The optical interface device as recited in claim 5, wherein said viewership meter comprises an audio matching circuit, said audio matching circuit comparing a first audio signal of a predetermined channel tuned by said viewership collection meter with a second audio signal output by a television to which said set-top converter is connected, wherein if said first audio signal and said second audio signal match, said viewership collection meter determines that said channel to which said set-top converter box is tuned is said predetermined channel

7 The optical interface device as recited in claim 1, wherein said light receiving elements comprise phototransistors and said electronic display comprises seven- segment elements, wherein said phototransistors aie turned ON and OFF in response to receiving incident light from said seven-segment elements, and wherein said signals comprise one of a logic high and a logic low state

8 The optical interface device as recited in claim 7, wherein said optical interface device is adapted to be mounted to said electronic display such that each of said phototransistors are arranged to receive light from one segment of each seven-segment display element

9 The optical interface device as recited in claim 8, wherein said seven- segment elements comprise LED display elements

10 The optical interface device as recited in claim 7, wherein said optical interface device is adapted to receive power and additional data via said second electrical connection

11. The optical interface device as recited in claim 1 , said optical interface device comprising an optically clear material, wherein said electronic display is visible through said optical interface.

12. The optical interface device as recited in claim 1 , wherein said optical interface device defines cut-out regions such that information displayed by said electronic display is visible to the television viewer through said cut-out regions

13 A system for determining viewership of channels tunable by a set-top converter box having an electronic display, said system comprising an optical interface device which receives light emitted from said electronic display; and aviewership collection meter connected to said optical interface device, said viewership meter periodically storing a channel to which said set-top converter is tuned, wherein said channel to which said set-top converter is tuned is determined by said optical interface device and communicated to said viewership collection meter, and wherein said viewership collection meter stores said channel and forwards it to a predetermined location at selected times

14. Thesystem for determining viewership of channels tunable by a set-top converter box as recited in claim 13, wherein said viewership collection meter further comprises an audio matching circuit, said audio matching circuit comparing a first audio signal of a predetermined channel tuned by said viewership collection meter with a second audio signal output by a television to which said set-top converter is connected, wherein if said first audio signal and said second audio signal match, said viewership collection meter determines that said channel to which said set-top converter box is tuned is said predetermined channel.

15. The system for determining viewership of channels tunableby a set-top converter box as recited in claim 13, wherein said optical interface device comprises phototransistors and said electronic display comprises seven-segment elements, wherein said phototransistors are turned ON and OFF m response to incident light from said seven-segment elements, and wherein said phototransistors output signals that comprise one of a logic high and a logic low state to indicate the presence or absence of incident light

16 The system for determining viewership of channels tunable by a set-top converter box as recited in claim 15, wherein said optical interface device is adapted to be mounted to said electronic display such that each of said phototransistors are arranged to receive light from one segment of each seven-segment display element

17 The system for determining viewership of channels tunableby a set-top converter box as recited in claim 16, wherein said seven-segment elements comprise LED display elements

18 A method of determining a channel to which a set-top converter box is tuned using a optical interface, said set-top converter comprising an electronic display that is driven by drive signals, said method comprising receiving light for said electronic display at said optical interface, outputting signals from said optical interface representative of received light, determining a channel to which said set-top converter box is tuned by sampling said signals, generating a coded representation of said determined channel, and outputting said coded representation

19 The method as recited in claim 18, wherein said electronic display comprises at least one seven-segment display element, said step of determining a channel to which said set-top converter box is tuned further comprising (a) determining which segments of said seven-segment display element is illuminated, (b) determining a character being displayed by said seven-segment display element; and

(c) repeating steps (a) and (b) for each seven-segment display element in said electronic display.

20. The method as recited in claim 18, wherein said step of generating a coded representation of said determined channel comprises generating an ASCII value of said channel to which said set-top converter box is tuned.

21. The method as recited in claim 20, wherein said step of outputting said coded representation comprises serially transmitting said ASCII value to a viewership meter.

22. The method as recited in claim 21 , further comprising: storing, at said viewership meter, said ASCII value; and forwarding said ASCII value at predetermined times to a central collection site.