JP3084700U - television - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To adjust white balance of a SECAM video only within a predetermined range, it is not possible to sufficiently adjust the white balance of a SECAM video. Was. A video display means for generating a video signal so as to adjust a white balance of a video based on a white balance adjustment value within a predetermined range corresponding to a television signal of a second broadcast system and displaying the video. On the other hand, when it is determined to be the second broadcast system, the white balance adjustment value read from the non-volatile memory is corrected to adjust the white balance of the video based on the television signal of the second broadcast system for each television, The corrected white balance adjustment value and the second broadcast adjustment value read from the nonvolatile memory are output. It is possible to sufficiently adjust the white balance of the video image corresponding to the second broadcast system.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 The present invention relates to a television, and more particularly, to a television that inputs television signals according to a plurality of broadcast systems and displays an image.

[0002]

[Prior art]

 Conventionally, this type of television receives a television broadcast signal of the PAL system and the SECAM system by a tuner to create an intermediate frequency signal, and a chroma IC creates a video signal from the intermediate frequency signal to receive an image. Video is being displayed from the tube. The tuner and the chroma IC are connected via an IIC bus to a microcomputer storing a program for controlling an internal circuit of the television. The EEPROM stores a white balance adjustment value for separately adjusting the white balance of a video based on a PAL television broadcast signal for each television and a black level of a video based on a SECAM television broadcast signal. A SECAM black level adjustment value to be adjusted separately for each one is stored. The EEPROM also stores a ROM correction program created so as to correct a defect in a program stored in the ROM in the microcomputer in the final adjustment process in the factory that manufactures the television. The microcomputer controls the tuner and the chroma IC based on the program stored in the ROM and the ROM correction program stored in the EEPROM.

Here, the microcomputer outputs the white balance adjustment value to the chroma IC when the microcomputer determines that the broadcast system of the television broadcast signal is the PAL system based on the program and the ROM correction program. I do. Then, the chroma IC obtains the white balance adjustment value and creates a video signal so as to adjust the white balance of the displayed image based on the white balance adjustment value. On the other hand, when it is determined that the broadcast system of the television broadcast signal is the SECAM system, the white balance adjustment value and the SECAM black level adjustment value are output to the chroma IC. Then, the chroma IC adjusts the white balance of the video based on the white balance adjustment value and the SECAM black level adjustment value within a predetermined range corresponding to the television broadcast signal of the SECAM system based on the white balance adjustment value. Create a video signal as follows. As a result, the white balance of the video based on the PAL television broadcast signal is adjusted, and the white balance of the video based on the SECAM television broadcast signal within a predetermined range is adjusted. Can be.

[0004]

[Problems to be solved by the invention]

 The above-mentioned conventional television has the following problems. That is, when the above-mentioned chroma IC is used, the white balance of the video based on the SECAM television broadcast signal can be adjusted only within a predetermined range. It could not be adjusted. Also, a technique disclosed in Japanese Patent Application Laid-Open No. 8-509346 is known, which controls the timing of the system clock by using an offset value, and ensures that the white balance of the video corresponding to the SECAM method is sufficient. Not applicable to tasks that adjust to Further, a technique disclosed in Japanese Patent Publication No. 6-83097 is also known. In this technique, each part of a television circuit is added with a standard value common to television and an offset value obtained as a result of a user operation. It is intended to make it easy to return the setting data to the standard value by adjusting the setting data. Therefore, the problem of sufficiently adjusting the white balance of a video based on a SECAM television broadcast signal by using a white balance adjustment value set for each television and corresponding to the PAL system for the chroma IC is used. On the other hand, the technology cannot be applied.

[0005] The present invention has been made in view of the above-mentioned problems, and is intended for inputting a television signal in a plurality of broadcasting systems and displaying an image, and displaying a television signal of a first broadcasting system such as the PAL system. It is possible to sufficiently adjust the white balance when a television signal of the second broadcast system such as the SECAM system is input while using a white balance adjustment value for adjusting the white balance of the video according to the above. The purpose is to provide television.

[0006]

[Means for Solving the Problems]

 In order to achieve the above object, the invention according to claim 1 includes a tuner for inputting a television broadcast signal according to the PAL system and the SECAM system to generate and output an intermediate frequency signal, and a PAL provided separately for the present television. A white balance adjustment value for adjusting the white balance of an image based on a television broadcast signal of a television system and a SECAM black level adjustment value provided for each television and for adjusting the black level of an image based on a television broadcast signal of the SECAM system. A video signal is generated and output from the stored EEPROM and the intermediate frequency signal input from the tuner based on the input white balance adjustment value so as to adjust the white balance of the video based on the television broadcast signal. And the above SECAM black level adjustment value is input. In this case, the video signal from the intermediate frequency signal is adjusted by the SECAM black level adjustment value so that the white balance of the video based on the white balance adjustment value is adjusted within a predetermined range corresponding to the SECAM television broadcast signal. IC for generating and outputting a signal, a picture tube discharge circuit for displaying an image based on the video signal output from the chroma IC, and a ROM storing a program for controlling an internal circuit of the television. The EEPROM has a correction program created so as to correct a defect of the program stored in the ROM in the final adjustment process of the television, and the microcomputer has: On the basis of the program stored in the ROM and the correction program stored in the EEPROM, The tuner and the chroma IC are controlled, and the broadcast system of the television broadcast signal is determined. When the broadcast system is determined to be the PAL system, the white balance adjustment value is read out from the EEPROM and the chroma IC is transmitted to the chroma IC. Output, and when it is determined that the above-mentioned SECAM method is used, the white balance adjustment value and the SECAM black level adjustment value are read out from the EEPROM and output to the chroma IC. Includes an offset value for SECAM that is provided for each television and adjusts the white balance of the video based on the SECAM television transmission signal by adding to the white balance adjustment value for each television. , The above microcomputer When the broadcasting method of the television broadcast signal is determined to be the SECAM method, the white balance adjustment value is added to the white balance adjustment value based on the SECAM offset value based on the correction program stored in the EEPROM. The balance adjustment value is corrected, and the corrected white balance adjustment value is output to the chroma IC. The chroma IC is used by the tuner based on the corrected white balance adjustment value input from the microcomputer. A video signal is generated and output from the intermediate frequency signal from the computer so as to adjust the white balance of the video based on the SECAM television broadcast signal.

In the invention according to claim 1 configured as described above, the tuner inputs a television broadcast signal according to the PAL system and the SECAM system, creates and outputs an intermediate frequency signal. The microcomputer has a ROM storing a program for controlling the internal circuit of the television. The EEPROM includes a white balance adjustment value that is provided for each television and adjusts a white balance of a video based on a PAL television broadcast signal, and a video that is provided for each television and is based on a SECAM television broadcast signal. The SECAM black level adjustment value for adjusting the black level of is stored. Further, a correction program created so as to correct a defect of the program stored in the ROM in the final adjustment step of the television is also stored. The microcomputer controls the tuner and the chroma IC based on the program stored in the ROM and the correction program stored in the EEPROM.

[0008] The chroma IC creates a video signal based on a white balance adjustment value input from a microcomputer so as to adjust a white balance of a video based on a television broadcast signal from an intermediate frequency signal input from a tuner. Output. Then, the picture tube discharge circuit displays an image based on the output image signal. Further, when the SECAM black level adjustment value is input, the chroma IC adjusts the white balance of the video based on the white balance adjustment value by the SECAM black level adjustment value in accordance with the SECAM system television broadcast signal. Create and output a video signal from the intermediate frequency signal to adjust within the range. The picture tube discharge circuit displays an image based on the output image signal. The microcomputer determines the broadcast system of the television broadcast signal based on the program stored in the ROM and the correction program stored in the EEPROM. When the broadcast system of the television broadcast signal is determined to be the PAL system, the white balance adjustment value is read from the EEPROM and output to the chroma IC. Then, the chroma IC can adjust the white balance of the video based on the PAL television broadcast signal for each television based on the white balance adjustment value.

Here, the correction program stored in the EEPROM is provided for each television and adds the white balance adjustment value to the white balance of the video based on the television broadcast signal of the SECAM system. Includes SECAM offset values that are adjusted for each zone. Therefore, when the microcomputer determines that the broadcast system of the television broadcast signal is the SECAM system, the microcomputer reads out the white balance adjustment value and the SECAM black level adjustment value from the EEPROM and performs the SECAM offset based on the correction program. The white balance adjustment value is corrected by adding the value to the white balance adjustment value, and the corrected white balance adjustment value and the read SECAM black level adjustment value are output to the chroma IC. Then, the chroma IC adjusts the white balance of the video based on the corrected white balance adjustment value by the SECAM black level adjustment value within a predetermined range corresponding to the television broadcast signal of the SECAM system. A video signal is created from the inter-frequency signal and output.

That is, the white balance adjustment value itself is modified so as to adjust the white balance of an image based on a SECAM television broadcast signal for each television. In other words, the chroma IC can sufficiently adjust the white balance of an image to be displayed on the picture tube discharge circuit in a predetermined range in accordance with the SECAM television broadcast signal. Therefore, when displaying the video by inputting the PAL and SECAM television broadcast signals, the SECAM is used while using the white balance adjustment value for adjusting the white balance of the video by the PAL television broadcast signal. The white balance can be adjusted sufficiently even when a television broadcast signal of the system is input. Further, when the operation of the program stored in the ROM of the microcomputer is corrected, the correction program stored in the rewritable EEPROM may be corrected, so that the convenience is improved. As a result, when correcting the white balance adjustment value, it is not necessary to correct the program stored in the non-rewritable ROM, but only the correction program stored in the rewritable EEPROM. Therefore, it is not necessary to replace the microcomputer having the ROM, and it becomes easy to adjust the white balance of the image by the television broadcast signal of the SECAM system for each television.

By the way, the present invention can be applied to a television that inputs television signals of a plurality of broadcasting systems and displays an image. Therefore, the invention according to claim 2 is directed to a tuner means for inputting a television signal according to a plurality of broadcasting systems, generating and outputting an intermediate frequency signal, and a television system of a first broadcasting system provided separately for the present television. A non-volatile storage of a white balance adjustment value for adjusting the white balance of an image based on a signal and an adjustment value for a second broadcast which is provided separately for this television and adjusts an image based on a television signal of a second broadcast system. A video signal is generated by adjusting a white balance of a video based on the television signal from the intermediate frequency signal input from the tuner means based on the memory and the input white balance adjustment value. Is displayed, and when the adjustment value for the second broadcast is input, the white balance is adjusted by the adjustment value for the second broadcast. Display means for creating a video signal from the intermediate frequency signal and displaying the video so that the white balance of the video based on the video adjustment value is adjusted within a predetermined range corresponding to the television signal of the second broadcast system. Determining the broadcast system of the television signal, and when determining the first broadcast system, reads out the white balance adjustment value from the non-volatile memory and outputs it to the video display means; If it is determined that the broadcast method is the same as the broadcast method, the white balance adjustment value and the adjustment value for the second broadcast are read from the non-volatile memory, and the read white balance adjustment value is used as the white color of the video based on the television signal of the second broadcast method. The balance is adjusted so that it is adjusted for each television, and the corrected white balance adjustment value and the readout adjustment for the second broadcast The door is a configuration you and a white balance control means for outputting to said image display means.

[0012] In the invention according to claim 2 configured as described above, the tuner means inputs a television signal according to a plurality of broadcasting systems, creates an intermediate frequency signal, and outputs the intermediate frequency signal. The nonvolatile memory has a white balance adjustment value for adjusting the white balance of an image based on the television signal of the first broadcast system, and a second broadcast adjustment value for adjusting the image based on the television signal of the second broadcast system. The adjustment value is stored. Note that the white balance adjustment value and the second broadcast adjustment value are provided separately for this television. The white balance control means determines a broadcast system of the television signal. When it is determined that the broadcast system of the television signal is the first broadcast system, the white balance adjustment value is read from the nonvolatile memory and output to the video display means. Then, based on the white balance adjustment value input from the white balance control means, the video display means adjusts the video signal white balance of the video based on the television signal from the intermediate frequency signal input from the tuner means. Create and display the video. That is, the white balance of the video based on the television signal of the first broadcast system can be adjusted for each television.

When the white balance control means determines that the broadcast system of the television signal is the second broadcast system, the white balance adjustment value and the second broadcast adjustment value are read out from the nonvolatile memory, and the second broadcast system is read. The white balance adjustment value is adjusted so that the white balance of the video based on the television signal of the second television is adjusted for each television, and the corrected white balance adjustment value and the readout adjustment value for the second broadcast are displayed on the video display means. Output to The video display means creates a video signal based on the white balance adjustment value input from the white balance control means so as to adjust the white balance of the video based on the television signal from the intermediate frequency signal input from the tuner means. When displaying a video, the tuner adjusts the white balance of the video based on the white balance adjustment value within a predetermined range in accordance with the television signal of the second broadcast system, based on the input adjustment value for the second broadcast. A video signal is created from the intermediate frequency signal input from the means and the video is displayed. That is, the white balance of the video based on the television signal of the second broadcast system can be adjusted within a predetermined range for each television.

Here, the white balance adjustment value itself is modified so as to adjust the white balance of the video based on the television signal of the second broadcast system for each television. That is, the video display means can sufficiently adjust the white balance of the video displayed in correspondence with the television signal of the second broadcast system even within the predetermined range. Therefore, when displaying a video by inputting a television signal of a plurality of broadcast systems, the second white balance adjustment value for adjusting the white balance of the video by the television signal of the first broadcast system is used. White balance can be sufficiently adjusted when a broadcast-type television signal is input.

[0015] The television signal may be a television broadcast signal that is a broadcast wave or a signal that is input from an external device. The tuner means only needs to be capable of inputting television signals of a plurality of broadcasting systems to generate and output an intermediate frequency signal, and may be constituted by a one-chip IC or by combining a plurality of circuit elements. You may. The image display means may be composed of a chroma IC and a predetermined picture tube discharge circuit having a picture tube, or may be composed of a signal amplifier circuit combining a plurality of circuit elements instead of the chroma IC. There are various methods for adjusting the white balance, such as adjusting the voltage applied to the cathode and grid of the picture tube, the amount of current of each color beam, and instructing the chroma IC to output signals of each color. This can be realized by relatively changing the level of the color difference signal and the like. The television to which the present invention is applied may be a single device, a device attached to another device, or a device integrated with another device. Therefore, the present invention can be applied to an apparatus in which a video deck and a television are integrated, and an apparatus in which a DVD and a television are integrated.

By the way, as an example of a configuration for correcting a white balance adjustment value itself for adjusting a white balance of a video based on a television signal of a first broadcast system, the invention according to claim 3 is based on the nonvolatile memory. The correction value for correcting the white balance adjustment value so as to adjust the white balance of the video based on the television signal of the second broadcast system for each television is stored. The means reads the correction value from the non-volatile memory when determining the broadcast system of the television signal from the second broadcast system, and corrects the white balance adjustment value based on the read correction value. Output to the video display means. That is, based on the correction value stored in the nonvolatile memory, the white balance adjustment value is corrected so as to adjust the white balance of the video based on the television signal of the second broadcast system for each television. Can be. Therefore, the configuration is simplified.

Further, as an example of the configuration of the correction value, the invention according to claim 4 is characterized in that the correction value is added to the white balance adjustment value to obtain a video based on the television signal of the second broadcast system. An offset value for adjusting a white balance for each television. The white balance control means, when judging the transmission method of the television signal to be the second broadcasting method, reads the offset from the nonvolatile memory. The value is read and added to the white balance adjustment value to correct the white balance adjustment value, and the corrected white balance adjustment value is output to the video display means. In other words, it is possible to provide a simpler configuration in which the white balance adjustment value is corrected so that the white balance of the video based on the television signal of the second broadcast system is adjusted for each television.

As the non-volatile memory, various memories can be adopted as long as the memory is a non-volatile memory. As an example of the configuration, the invention according to claim 5 is configured such that the nonvolatile memory is a memory in which stored data can be rewritten. That is, since the contents of the non-volatile memory can be rewritten, it becomes easy to update the white balance adjustment value and the black level adjustment value. Here, the rewritable nonvolatile memory may be an EEPROM or an EPROM. Of course, a non-rewritable ROM can be used for the non-volatile memory in consideration of manufacturing costs and the like.

When a program for controlling an internal circuit of a television is stored in a ROM, a program for modifying the program may be stored in a rewritable nonvolatile memory. In view of the above, the invention according to claim 6 is characterized in that the white balance control means has a ROM storing a program for controlling an internal circuit of the television, and the rewritable nonvolatile memory includes the ROM. A correction program created so as to correct a defect of the stored program is stored, and the white balance control means executes the second broadcast system based on the correction program stored in the rewritable nonvolatile memory. The white balance adjustment value is corrected so as to adjust the white balance of the video based on the television signal for each of the televisions, and the corrected white balance is output to the video display means. That is, when the operation of the program stored in the non-rewritable ROM is modified, the modification program stored in the rewritable nonvolatile memory may be modified, so that the convenience is improved. Further, when correcting the white balance adjustment value, it is not necessary to correct the program stored in the non-rewritable ROM, and it is sufficient to correct the correction program stored in the rewritable nonvolatile memory. It becomes easy to adjust the white balance of the image by the television signal of the second broadcast system for each television.

By the way, as an example of the adjustment value for the second broadcast, the invention according to claim 7 is that the adjustment value for the second broadcast is provided for the television signal of the second broadcast system provided separately for the main television. It is configured to be a black level adjustment value for adjusting the black level of the video based on the video. That is, an example of the adjustment value for the second broadcast can be provided, and the video display means can adjust the white balance of the video based on the white balance adjustment value by the black level adjustment value so as to correspond to the television signal of the second broadcast system. Thus, a video signal can be generated from the intermediate frequency signal so that the video is displayed within a predetermined range.

[0021] Further, as an example of a plurality of television signal broadcast systems, the invention according to claim 8 is characterized in that the first broadcast system television signal is a PAL system television signal and the second broadcast system is a PAL system television signal. The television signal of the second broadcast system is configured to be a television signal of the SECAM system. That is, an example of a plurality of broadcasting methods can be provided, and the image display means, when the adjustment value for the second broadcast is input, adjusts the white balance of the image based on the white balance adjustment value by the adjustment value for the second broadcast. A video signal can be created from an intermediate frequency signal to display a video so that the balance is adjusted within a predetermined range in accordance with a SECAM television signal.

[0022]

[Effect of the invention]

 As described above, according to the present invention, when a PAL and SECAM television broadcast signal is input and a video is displayed, a white balance adjustment value for adjusting the white balance of the video by the PAL television signal is displayed. It is possible to provide a television capable of sufficiently adjusting a white balance when a SECAM television broadcast signal is input while using the television broadcast signal. In addition, when correcting the white balance adjustment value, the correction program stored in the rewritable EEPROM may be corrected, so that there is no need to replace the microcomputer, and it is possible to use a SECAM television broadcast signal for each television. It is easy to adjust the white balance of the image. Further, according to the invention of claim 2, when displaying a video by inputting a television signal of a plurality of broadcast systems, the white balance of the video by the television signal of the first broadcast system is adjusted. It is possible to provide a television capable of sufficiently adjusting the white balance when a television signal of the second broadcast system is input while using the white balance adjustment value.

Further, according to the invention of the third aspect, the white balance adjustment value is modified so that the white balance of the video based on the television signal of the second broadcast system is adjusted for each television with a simple configuration. According to the invention of claim 4, a simpler configuration can be provided. Further, according to the invention of claim 5, it is possible to easily update the white balance adjustment value and the black level adjustment value. Further, according to the invention of claim 6, when the white balance adjustment value is corrected, the correction program stored in the rewritable nonvolatile memory may be corrected, so that the second broadcast system for each television can be corrected. It is easy to adjust the white balance of the image by the television signal.

Further, according to the invention of claim 7, it is possible to provide an example of the adjustment value for the second broadcast, and the image display means uses the black level adjustment value to adjust the white balance of the image based on the white balance adjustment value. Can be displayed in accordance with the television signal of the second broadcast system. Further, according to the invention of claim 8, it is possible to provide an example of a plurality of broadcast systems, and the video display means uses the second broadcast adjustment value when the second broadcast adjustment value is input. It is possible to display an image in which the white balance of the image based on the white balance adjustment value is adjusted in accordance with the SECAM television signal.

[0025]

[Embodiment of the invention]

 Hereinafter, embodiments of the present invention will be described in the following order. (1) Schematic configuration of the television according to the present invention: (2) Description of processing of the television: (3) Operation of the television:

(1) Schematic Configuration of Television According to the Present Invention: FIG. 1 is a schematic block diagram showing a configuration of a television 100 according to an embodiment of the present invention. In the figure, a television 100 includes a microcomputer 10, a tuner 20, which is a one-chip IC, a chroma IC 30, an EEPROM 40, a picture tube discharge circuit 50, an audio output circuit including an audio amplifier 61 and a speaker 62, an operation panel 15, and a remote control (not shown). , Etc. The microcomputer 10, the tuner 20, the chroma IC 30, and the EEPROM 40 are connected to an IIC bus, and these ICs can transmit and receive data via the IIC bus. Note that the tuner 20 and the chroma IC 30 are directly connected to the microcomputer 10 via another signal line, and operate under control based on a signal input from the microcomputer 10 via the signal line. .

An antenna 21 and a chroma IC 30 are connected to the tuner 20. A deflection circuit 53 and an audio amplifier 61 are connected to the chroma IC 30, and a cathode amplifier 51 is connected thereto via an on-screen display (OSD) circuit (not shown). The OSD circuit is also connected to the microcomputer 10 and can output an OSD display signal from the microcomputer 10 to the cathode amplifier 51. The picture tube 52 has a deflection coil 54 attached thereto and is connected to a cathode amplifier 51 and a flyback transformer (FBT) 55 so that a picture can be displayed. The speaker 62 is connected to the audio amplifier 61 and can output sound.

The microcomputer 10 includes a CPU 11, a ROM 12, a RAM 13, an I / O 14, and a timer circuit (not shown) connected to an internal bus. The ROM 12 stores a program for controlling an internal circuit of the television 100. Further, the EEPROM 40 stores a ROM correction program (correction program) created to correct the program stored in the ROM 12. The CPU 11 controls the entire television 100 in accordance with the correction program written in the ROM 12 or the EEPROM 40 connected via the IIC bus, thereby realizing a function as a television. For example, regarding the tuning control of the tuner 20, if the operation panel 15 or a remote controller (not shown) is operated to select a desired channel, the microcomputer 10 will select a channel using the operation panel 15 or an infrared receiver (not shown). Is detected, and the corresponding frequency data is sent to the tuner 20. Then, the tuner 20 tunes to the channel frequency based on the same frequency data.

The tuner 20 is capable of inputting television broadcast signals of the PAL system (first broadcast system) and the SECAM system (second broadcast system), creating an intermediate frequency signal, and outputting the intermediate frequency signal. is there. The tuner 20 is a so-called frequency synthesizer type tuner, and includes therein a high-frequency amplifier circuit, a local oscillator circuit, a mixing circuit, and the like (not shown). Of course, the use of the tuner by the frequency synthesizer system is merely an example, and the tuner may be, for example, a voltage synthesizer system. The high-frequency amplifier circuit has a band-pass filter. Under the control of the microcomputer 10, a television broadcast signal (television signal) that is a broadcast wave corresponding to a desired frequency from the antenna 21 via the band-pass filter via the antenna 21 Received and amplified to create a high-frequency signal. The high-frequency amplifier circuit receives a television broadcast signal according to the PAL system and the SECAM system and generates a high-frequency signal. The frequency of this high frequency signal is the same as the frequency of the television broadcast signal of the selected broadcast. The high frequency amplifier circuit outputs the generated high frequency signal to the mixing circuit.

The local oscillation circuit is constituted by a PLL (Phase Locked Loop) circuit. The PLL circuit generates a local oscillation signal having a local oscillation frequency corresponding to a desired frequency of a television broadcast signal, and generates the local oscillation signal in a mixing circuit. Output. The mixing circuit mixes the output from the high-frequency amplifier circuit and the local oscillation signal from the local oscillation circuit, converts the mixed signal into an intermediate frequency signal (IF), and outputs it to the chroma IC 30. That is, the tuner 20 constitutes a tuner means for inputting a television signal according to a plurality of broadcast systems, generating an intermediate frequency signal, and outputting the intermediate frequency signal. As the high-frequency amplifier circuit, the local oscillation circuit, and the mixing circuit, various television circuits that have been conventionally used can be applied.

FIG. 2 is an explanatory diagram for explaining a difference between television broadcast signals between the PAL system and the SECAM system. In the figure, a television broadcast signal is schematically shown with the horizontal direction as a time axis.In the case of a television broadcast signal by radio waves, such a signal is actually broadcast while being superimposed on a carrier wave for each channel. Have been. The television broadcast signal is composed of a periodic synchronizing signal and a video signal for forming an image on each scanning line. The synchronizing signal includes a vertical synchronizing signal Vsync and a horizontal synchronizing signal Hsync. The vertical synchronizing signal Vsync is a pulse-like signal superimposed so as to define the period of one field, and the horizontal synchronizing signal Hsync is a pulse-like signal superimposed so as to define the period of each scan line. Signal. A burst signal for demodulating the carrier chrominance signal is superimposed on the back porch of the horizontal synchronization signal Hsync. The frequency of the vertical synchronizing signal is the same as 50 Hz in the PAL system and the SECAM system. On the other hand, the frequency of the burst signal is different between the PAL system and the SECAM system. In the PAL system, the frequency is 4.43 MHz. In the SECAM system, burst signals having frequencies of 4.25 MHz and 4.41 MHz are alternately superimposed. I have.

The chroma IC 30 to which the intermediate frequency signal from the tuner 20 is input is generally configured as shown in FIG. 3, and performs various signal processing. The chroma IC 30 is a one-chip IC, and includes an intermediate frequency amplification (VIF) circuit 31, a detection circuit 32, a synchronization circuit 33, a burst signal detection unit 34, a PAL system demodulation unit 35, a SECAM system demodulation unit 36, and a white balance adjustment unit. 37, etc. The intermediate frequency signal from the tuner 20 is input to the VIF circuit 31. The VIF circuit 31 amplifies the intermediate frequency signal by an intermediate frequency and outputs the amplified signal to the detection circuit 32. A VCO (Voltage Controlled Oscillator) circuit (not shown) is connected to the detection circuit 32, and the VCO circuit oscillates an oscillation signal based on a reference oscillation signal input from a crystal oscillation circuit and outputs the oscillation signal to the detection circuit 32. . Here, the VCO circuit can change the oscillation frequency of the oscillation signal according to the voltage input from the microcomputer 10.

The detection circuit 32 performs video detection while synchronizing with the oscillation frequency of the oscillation signal from the intermediate frequency signal amplified by the intermediate frequency, separates the composite video signal, and outputs the synthesized video signal to the burst signal detection unit 34. As for the audio signal, a second audio intermediate frequency signal is created by mixing the audio component and the oscillating signal in the intermediate frequency signal amplified by the intermediate frequency, and is subjected to FM detection to be an AUDIO signal. Output. Further, the detection circuit 32 also generates a horizontal / vertical synchronization signal (SYNC) based on the oscillation frequency of the oscillation signal during the detection process and outputs the signal to the synchronization circuit 33. The synchronization circuit 33 creates a sawtooth-shaped DRIVE signal based on the input horizontal / vertical synchronization signal, and outputs the signal to a deflection circuit 53 including a horizontal deflection circuit and a vertical deflection circuit. At this time, processing is performed based on a signal representing a white balance adjustment value input from the white balance adjustment unit 37. As the VIF circuit, the VCO circuit, the detection circuit, and the synchronizing circuit, various television circuits conventionally used can be applied.

The burst signal detector 34 to which the composite video signal from the detection circuit 32 is input determines whether the burst signal in the composite video signal has a certain frequency. Here, when the burst signal has a fixed frequency, the television broadcast signal input to the tuner 20 is of the PAL system, and when the burst signal is not of a constant frequency, the television broadcast signal is of the SECAM system. Further, the burst signal detection unit 34 outputs a signal to the microcomputer 10 for determining whether or not the burst signal has a fixed frequency. Therefore, the microcomputer 10 can determine the broadcast system of the television broadcast signal by determining this signal.

The composite video signal input to the burst signal detector 34 is output to the PAL demodulator 35 when the burst signal is determined to have a constant frequency, and the burst signal is If it is determined that it is not, it is output to the SECAM method demodulation unit 36. The demodulation units 35 and 36 are circuits that perform predetermined color demodulation processing corresponding to the PAL system and the SECAM system, respectively, on the input composite video signal, and output a luminance signal (Y) and an RGB signal. is there. Here, the PAL demodulation unit 35 separates the luminance signal and the carrier chrominance signal, generates a subcarrier from the burst signal, and demodulates the carrier chrominance signal with the subcarrier appropriately to obtain a color difference signal. At this time, processing is performed based on various signals representing white balance adjustment values input from the white balance adjustment unit 37. The SECAM demodulator 36 applies a bell filter (not shown) to the SECAM composite video signal, and demodulates the carrier chrominance signal while appropriately switching the subcarrier frequency during demodulation based on the timing of the horizontal synchronization signal. Then, a color difference signal is obtained. Also, the luminance signal is separated via a predetermined filter. At this time, processing is performed based on the white balance adjustment value input from the white balance adjustment unit 37 and various signals representing the SECAM black level adjustment value. Each of the demodulation units 35 and 36 generates an RGB signal from the color difference signal and the luminance signal, and outputs the RGB signal and the luminance signal to the picture tube discharge circuit 50.

The white balance adjustment unit 37 holds a white balance adjustment value and a SECAM black level adjustment value input from the microcomputer 10 and outputs a signal to each of the demodulation units 35 and 36 and the synchronizing circuit 33, and a picture tube. This circuit outputs a signal for adjusting the cutoff to the discharge circuit 50. Therefore, according to an instruction from the microcomputer 10, the white balance of the video displayed on the picture tube 52 can be adjusted while the white balance adjusting unit 37 adjusts the luminance signal and the RGB signal according to the broadcast system of the television broadcast signal. .

The luminance signal and the RGB signals output from the chroma IC 30 are output to the cathode amplifier 51, amplified by the cathode amplifier 51, and supplied to the picture tube 52. On the other hand, the AUDIO signal is output to an audio amplifier 61, amplified by the audio amplifier 61, and supplied to a speaker 62. Then, the speaker 62 outputs a sound based on the amplified AUDIO signal. The deflection circuit 53 generates a predetermined horizontal / vertical drive current corresponding to the horizontal / vertical drive signal, and supplies the current to the deflection coil 54 attached to the picture tube 52, thereby causing the electron beam to move in the horizontal / vertical direction. Drive. A high-frequency signal generated in the horizontal deflection circuit is supplied to the FBT 55, and a high voltage to be supplied to the picture tube 52 is generated. As a result, in the picture tube 52, an electron beam corresponding to the amplified luminance signal and the RGB signal is emitted while being driven, and an image is displayed on the surface of the picture tube 52. The chroma IC 30 and the picture tube discharge circuit 50 constitute a video display means according to the present invention.

As shown in the schematic diagram of FIG. 4, the EEPROM 40, which is a nonvolatile memory in which data to be stored according to the present invention is rewritable, has a white balance adjustment value and a SECAM black level adjustment according to the present invention. A data area storing data such as values (second broadcast adjustment values) and the like and a ROM collection area storing a ROM correction program are provided. The white balance adjustment value stored in the EEPROM 40 is a value for adjusting the white balance of a video based on a PAL television broadcast signal (hereinafter, referred to as a PAL video), and includes an R adjustment value and a G adjustment value. , B adjustment value, cutoff adjustment value, and drive adjustment value. The SECAM black level adjustment value stored in the EEPROM 40 is a value (black level adjustment value) for adjusting the black level of a video (hereinafter, referred to as a SECAM video) based on a SECAM television broadcast signal. ), And there are two types of RY adjustment values and BY adjustment values. Each white balance adjustment value and each SECAM black level adjustment value are set for each television 100. Therefore, these adjustment values are slightly different for each television 100.

When these adjustment values are stored in the EEPROM 40, the following may be performed. That is, in a final adjustment process in a factory where the television 100 is manufactured, a test signal generator for generating a predetermined test signal, a display color of an image of the picture tube 52, and the like are measured and digitized in the television 100. Connect a computer for external input to which a color analyzer is connected. Then, the operation mode is set to the factory mode by simultaneously pressing a plurality of operation buttons that are not normally operated on the operation panel 15 or the remote controller. First, a test signal generator generates a test signal corresponding to a PAL television broadcast signal, and an external input computer obtains the R adjustment value, the G adjustment value, and the B adjustment value from the image of the picture tube 52 or the like. , A cut-off adjustment value, and a drive adjustment value, and writes these white balance adjustment values in a predetermined area of the EEPROM 40 via the IIC bus in the television 100. Next, a test signal generator generates a test signal corresponding to the SECAM television broadcast signal, and an external input computer obtains the RY adjustment value and the BY adjustment from the video of the picture tube 52 and the like. The values are obtained, and these SECAM black level adjustment values are written to a predetermined area of the EEPROM 40 via the IIC bus in the television 100.

The ROM correction program stored in the EEPROM 40 is a program created so as to correct a defect of a program for controlling an internal circuit of the television 100 stored in the ROM 12 in the microcomputer 10. Since the contents of the ROM 12 cannot be rewritten, changing the contents of the ROM 12 requires replacing the microcomputer 10 itself. Therefore, a ROM correction program for modifying the contents of the program stored in the ROM 12 is stored in the rewritable EEPROM 40, and the ROM correction program is appropriately executed so that the microcomputer 10 does not need to be replaced. I have. The ROM collection program is also written in the EEPROM 40 from the external input computer connected to the television 100 via the IIC bus in the final adjustment process in the factory where the television 100 is manufactured.

The microcomputer 10 controls the tuner 20 and the chroma IC 30 based on a program stored in the internal ROM 12 and a ROM correction program stored in the EEPROM 40. Then, the broadcast system of the television broadcast signal input to the tuner 20 is determined based on the signal output from the burst signal detection unit 34 of the chroma IC 30. When the microcomputer 10 determines that the broadcast system of the input television broadcast signal is the PAL system, the microcomputer 10 reads the white balance adjustment value adjusted corresponding to the PAL system image for each television 100 from the EEPROM 40 and sends the read white balance adjustment value to the chroma IC 30. Output. Then, the chroma IC 30 holds the input white balance adjustment value in the white balance adjustment unit 37. Then, based on the held white balance adjustment value, the luminance signal, the RGB signal, the cutoff signal, and the DRIVE signal are adjusted so as to adjust the white balance of the PAL video from the intermediate frequency signal input from the tuner 20. A video signal composed of signals is created and output to the picture tube discharge circuit 50. That is, the RGB signal and the brightness signal are adjusted from the R adjustment value, the G adjustment value, and the B adjustment value, the cutoff signal for determining the retrace period of the picture tube 52 is adjusted from the cutoff adjustment value, and the drive adjustment value is adjusted. The DRIVE signal is adjusted. The picture tube discharge circuit 50 displays a PAL video based on the adjusted luminance signal, RGB signal, cutoff signal, and DRIVE signal. In this way, it is possible to adjust the white balance to the optimum state for each television 100 for the PAL system video.

By the way, in the conventional television, when the microcomputer 10 determines that the broadcasting system of the inputted television broadcasting signal is the SECAM system, the microcomputer 40 reads the two kinds of SECAM black levels together with the five kinds of white balance adjustment values from the EEPROM 40. The adjustment value was read out and output to the chroma IC 30. In the chroma IC 30, when the SECAM black level adjustment value is input, the video signal is generated so as to adjust the white balance of the video based on the television broadcast signal from the intermediate frequency signal based on the input white balance adjustment value. When outputting the video signal from the intermediate frequency signal, the white balance of the video based on the white balance adjustment value is adjusted within a predetermined range corresponding to the television broadcast signal of the SECAM system by the SECAM black level adjustment value. Is created and output. This is shown in the schematic diagram of FIG. In the figure, the white balance adjustment unit 37 adjusts the R signal output from the chroma IC 30 based on the R adjustment value as the white balance adjustment value and the RY adjustment value as the SECAM black level adjustment value. FIG. 2 is a block diagram schematically showing a circuit to be used. Although not shown, the white balance adjustment unit 37 is also provided with a circuit for adjusting the G and B signals, the luminance signal, the cutoff signal, and the DRIVE signal output from the chroma IC 30.

For example, when “100” is written in the EEPROM 40 as the R adjustment value, the microcomputer 10 outputs the R adjustment value “100” to the chroma IC 30. This R adjustment value adjusts the R of the PAL video to an optimum state. When displaying the PAL video, the white balance adjustment unit 37 sends the R adjustment value “100” to the PAL demodulation unit 35. Is output. However, the R adjustment value is not always in an optimum state for the R of the SECAM video. Therefore, in order to cope with the SECAM method, the white balance adjusting unit 37 adjusts the R adjustment value within a predetermined range (for example, within a range of -5 to +5) based on the RY adjustment value by the R adjustment circuit 37a. Fine adjustment is possible. For example, when a value corresponding to “+5”, which is the upper limit of the adjustment range, is written in the EEPROM 40 as the RY adjustment value, the microcomputer 10 sends the RY adjustment value corresponding to “+5” to the chroma IC 30. Is output. The R adjustment circuit 37a obtains an R-Y adjustment signal corresponding to “+5” corresponding to the R-Y adjustment value, and converts the R adjustment signal corresponding to the R adjustment value “100” to an R adjustment signal corresponding to “+5”. A SECAM-R adjustment signal corresponding to “105” is created by adjusting with the −Y adjustment signal, and output to the SECAM system demodulation unit 36.

However, for example, when the SE CAM-R adjustment signal for sufficiently adjusting the R signal output from the chroma IC 30 corresponds to the R adjustment value “115”, the SECAM-R adjustment signal is input from the microcomputer 10. Since the R adjustment value can only be adjusted in the range of “−5 to +5” with respect to the R adjustment value “100”, it can be adjusted only up to the R adjustment value “105”. As described above, since the white balance can be adjusted only within a predetermined range with respect to the SECAM video, the white balance of the SECAM video cannot be sufficiently adjusted. Therefore, the television 100 corrects the white balance adjustment value corresponding to the PAL system so that the white balance of the video of the SECAM system is adjusted for each television 100, and reads the corrected white balance adjustment value and the read SECAM. The black level adjustment value is output to the chroma IC 30. This processing is performed in accordance with the ROM correction program, and the ROM correction program is stored in the ROM correction area of the EEPROM 40.

(2) Description of Process of Present Television: FIG. 6 is a schematic diagram showing a process in which the television 100 according to an embodiment of the present invention adjusts the white balance of a SECAM video. The microcomputer 10 performs processing for controlling the chroma IC 30 and the like based on the program stored in the internal ROM 12 and the ROM collection program stored in the EEPROM 40, and the flow shown in FIG. . A signal for determining whether or not the burst signal has a constant frequency is output from the burst signal detection unit 34 of the chroma IC 30 to the microcomputer 10. Therefore, the microcomputer 10 determines the broadcast system of the television broadcast signal based on the signal (step S110). That is, when the burst signal has a constant frequency, the television broadcast signal input to the tuner 20 is determined to be the PAL system, and when the burst signal is not the constant frequency, the television broadcast signal is determined to be the SECAM system. .

When the television broadcast signal is determined to be of the PAL system, the microcomputer 10 performs a process of reading a white balance adjustment value corresponding to the PAL system from the EEPROM 40 and outputting it to the chroma IC 30 according to a flow not shown. On the other hand, when the television broadcast signal is determined to be in the SECAM format, the microcomputer 10 reads out a white balance adjustment value and a SECAM black level adjustment value corresponding to the PAL format from the EEPROM (step S120). Next, the ROM correction program stored in the EEPROM 40 is started, and the read white balance adjustment value is corrected based on the SECAM offset value (correction value) (step S130). In step S130, a process of adding the SECAM offset value to the white balance adjustment value is performed based on the ROM collection program stored in the EEPROM.

Here, as shown in FIG. 4, the SECAM offset value is an offset value included in the ROM collection program, and is stored in the ROM collection area of the EEPROM 40 together with the ROM collection program. The SECAM offset values include five types of R offset values, G offset values, B offset values, cutoff-offset values, and drive-offset values. These offset values are provided for each of the five types of white balance adjustment values (R adjustment value, G adjustment value, B adjustment value, cutoff adjustment value, and drive adjustment value) provided for the television 100 and corresponding to the PAL system. Is used to adjust the white balance of the video of the SECAM system for each television 100 by adding this to the TV 100. Each SECAM offset value is determined for each television 100 in a final adjustment process in a factory where the television 100 is manufactured, is included in the ROM correction program, and connects the IIC bus in the television 100 from the external input computer. The data is written in the EEPROM 40 via the memory. Therefore, these adjustment values are slightly different for each television 100.

After step S130, the corrected white balance adjustment value and the SECAM black level adjustment value read from the EEPROM 40 are output to the chroma IC 30 (step S140). As described above, the microcomputer 10 determines the broadcast system of the television signal, and when determining the first broadcast system, reads out the white balance adjustment value from the non-volatile memory and outputs it to the video display means. When it is determined that the broadcast system is the same as the broadcast system, the white balance adjustment value and the adjustment value for the second broadcast are read from the nonvolatile memory, and the white balance of the video of the second broadcast system is read so as to be adjusted for each television. The white balance adjustment value is corrected, and the corrected white balance adjustment value and the read second broadcast adjustment value are output to the video display means. That is, white balance control means is configured. Then, the chroma IC 30 obtains the corrected white balance adjustment value and the SECAM black level adjustment value from the microcomputer 10, and converts the video white balance based on the corrected white balance adjustment value into a SECAM television broadcast signal. A video signal is created and output from the intermediate frequency signal so that it is adjusted within a predetermined range.

For example, when “100” is written to the EEPROM 40 as the R adjustment value of the white balance adjustment value and “10” is included as the R offset value of the SECAM offset value in the ROM correction program, the chroma IC 30 On the other hand, as shown in FIG. 7, the microcomputer 10 outputs a corrected R adjustment value "110" by adding "10" to "100". When a value corresponding to “+5”, which is the upper limit of the adjustment range, is written as the RY adjustment value in the EEPROM 40, the RY adjustment value corresponding to “+5” is supplied from the microcomputer 10 to the chroma IC 30. It is output. In the white balance adjustment unit 37, the R adjustment circuit 37a obtains the R-Y adjustment signal corresponding to “+5” corresponding to the R-Y adjustment value, and performs the R adjustment corresponding to the corrected R adjustment value “110”. The signal is adjusted by an RY adjustment signal corresponding to “+5” to create a SECAM-R adjustment signal corresponding to “115”, and is output to the SECAM system demodulation unit 36. Therefore, the R signal output from the chroma IC 30 is sufficiently adjusted in accordance with the SECAM system image.

As shown in FIG. 8, the G adjustment value, the B adjustment value, the cutoff adjustment value, and the drive adjustment value also include the G offset value, the B offset value, the cutoff-offset value, and the drive-offset, respectively. After being corrected by the value, it is output to the chroma IC 30. Then, based on the SECAM black level adjustment value and the corrected white balance adjustment value, the chroma IC 30 controls the G and B signals, the luminance signal, and the G signal and the B signal so that the white balance of the SECAM video is sufficiently adjusted. A cutoff signal and a DRIVE signal are created and output.

That is, the chroma IC 30 adjusts the white balance of the video based on the corrected white balance adjustment value within a predetermined range corresponding to the SECAM television broadcast signal based on the SECAM black level adjustment value. Then, a video signal is created from the intermediate frequency signal and output. Here, since the white balance adjustment value itself has been modified so as to adjust the white balance of the SECAM video for each television 100, the white balance of the SECAM video is sufficiently adjusted even within a predetermined range. It is possible to do it. Therefore, when displaying the video by inputting the PAL and SECAM television broadcast signals, the SECAM television broadcast signal is input while utilizing the white balance adjustment value for adjusting the white balance of the PAL video. In this case, the white balance can be sufficiently adjusted.

(3) Operation of the Television: The operation of the television 100 according to an embodiment of the present invention will be described below. FIG. 9 is a flowchart showing a process performed by the microcomputer 10 for adjusting the white balance of the PAL system and the SECAM system video. This flow is repeatedly executed in accordance with the program stored in the ROM 12 and the ROM correction program. First, the broadcast system of the television broadcast signal is determined based on a signal that determines whether or not the burst signal output from the burst signal detector 34 of the chroma IC 30 has a constant frequency (step S210). If the signal indicates that the signal is a burst signal having a certain frequency, the process proceeds to step S220, and a process of displaying a PAL video is performed.

In step S 220, five types of white balance adjustment values corresponding to the PAL method are read from the EEPROM 40. Then, the read white balance adjustment value is output to the chroma IC 30 (step S230), and the flow ends. Then, the chroma IC 30 holds the five types of input white balance adjustment values in the white balance adjustment unit 37. Then, based on the held white balance adjustment value, the luminance signal, the RGB signal, the cutoff signal, and the DRIVE signal are adjusted so as to adjust the white balance of the PAL video from the intermediate frequency signal input from the tuner 20. , And outputs it to the picture tube discharge circuit 50. As a result, it is possible to display on the picture tube 52 a video of the PAL system in which the white balance is adjusted.

On the other hand, if it is determined in step S 210 that the signal output from the burst signal detection unit 34 has been determined to be a burst signal having a non-constant frequency, the process advances to step S 240 to display a SECAM video. Perform processing. In step S240, five types of white balance adjustment values corresponding to the PAL system and two types of SECAM black level adjustment values corresponding to the SECAM system are read from the EEPROM 40. Next, the ROM collection program stored in the EEPROM 40 is started, and the five types of SECAM offset values are added to the read five types of white balance adjustment values (step S250). Then, each white balance adjustment value is corrected based on the SECAM offset value. Then, as described above, each corrected white balance adjustment value is a value for adjusting the white balance of the SECAM video for each television 100.

Then, after terminating the ROM correction program started in step S 250, the five types of white balance adjustment corrected based on the program stored in the ROM 12 and the ROM correction program stored in the EEPROM 40 are terminated. The value and the two types of SECAM black level adjustment values read from the EEPROM 40 are output to the chroma IC 30 (step S260), and the flow ends.

Then, the chroma IC 30 holds the five types of white balance adjustment values and the two types of SECAM black level adjustment values corrected by the white balance adjustment unit 37. Then, based on the held corrected white balance adjustment value and the SECAM black level adjustment value, the luminance signal is adjusted from the intermediate frequency signal input from the tuner 20 so as to adjust the white balance of the SECAM video. , An RGB signal, a cutoff signal, and a DRIVE signal, and outputs the same to the picture tube discharge circuit 50. Here, since the white balance adjustment value itself has been modified so as to adjust the white balance of the SECAM video for each television 100, the white balance of the SECAM video is sufficiently adjusted even within a predetermined range. It is possible to do. As a result, an image of the SECAM system in which the white balance is sufficiently adjusted for each television can be displayed on the picture tube 52. Further, when correcting the white balance adjustment value corresponding to the PAL method, it is not necessary to correct the program stored in the ROM 12 in the non-rewritable microcomputer, but to correct the ROM correction program stored in the rewritable EEPROM 40. Therefore, it is easy to adjust the white balance of the video of the SECAM system for each television.

The present invention is also applicable to televisions that display television images by inputting a plurality of television signals in a plurality of broadcast systems, and that are capable of receiving television broadcast signals in a PAL system and a SECAM system. The present invention is applicable to various televisions other than televisions for displaying images. For example, the present invention can be applied to a television that inputs a television broadcast signal using the NTSC system as a first broadcast system and the PAL system as a second broadcast system and displays an image. The present invention is also applicable to televisions that display television images by inputting television signals of three or more types of broadcasting systems. In this case, there are two or more types of second broadcasting systems according to the present invention. Become. Further, the television signal input to the television may be a broadcast signal transmitted as a broadcast wave or a signal input from an external device.

Here, the white balance adjustment value may be any value that adjusts the white balance of an image based on a television signal, and various adjustment values other than the above five combinations can be adopted. . Of course, it is not necessary to use all the five adjustment values described above. The black level adjustment value may be any value that adjusts the black level of the video based on the television signal of the second broadcast system, and various adjustment values other than the combination of the two types described above can be adopted. . When the white balance adjustment value is corrected, it can be corrected by various methods other than by adding the above-described SECAM offset value. For example, a coefficient for correcting the white balance adjustment value for each television can be stored in the EEPROM, and the correction can be performed by multiplying the coefficient by the white balance adjustment value. In addition, an arithmetic expression for correcting the white balance adjustment value for each television may be stored in the EEPROM, and the correction may be performed using the arithmetic expression. Further, in the above-described embodiment, the broadcast system of the television signal is determined based on the signal output from the burst signal detection unit in the chroma IC. However, the television is provided with a PAL / SECAM switch, and the state of the switch is determined. , The broadcast system of the television signal may be determined.

Further, in the above-described embodiment, the microcomputer controls the chroma IC or the like based on the program stored in the ROM in the microcomputer and the ROM correction program. However, the control program is stored in the EEPROM and the control is performed. Control of the chroma IC or the like may be performed based on a program. In this case, in order to save the trouble of correcting the control program, it is also possible to store the correction program for correcting the control program in the same EEPROM. Of course, when correcting the white balance adjustment value, the correction may be performed without using a correction program.

As described above, according to the present invention, when a television signal of a plurality of broadcast systems is input and an image is displayed, an image of a television signal of a first broadcast system such as the PAL system is used. A television capable of sufficiently adjusting the white balance when a television signal of the second broadcasting system such as the SECAM system is input, using the white balance adjustment value for adjusting the white balance of the television. Can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic block diagram showing a television according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram illustrating a difference between television broadcast signals between the PAL system and the SECAM system.

FIG. 3 is a block diagram illustrating a schematic configuration of a chroma IC.

FIG. 4 is a schematic diagram showing a storage area of an EEPROM.

FIG. 5 is a block diagram schematically illustrating a part of a white balance adjustment unit in a television according to a conventional example.

FIG. 6 shows a television according to an embodiment of the present invention.
It is a schematic diagram which shows the process which adjusts the white balance of the image of ECAM system.

FIG. 7 is a block diagram schematically illustrating a part of a white balance adjustment unit in the television according to the embodiment of the present invention;

FIG. 8 is a schematic diagram showing how each white balance adjustment value is corrected.

FIG. 9 is a flowchart illustrating a process of adjusting a white balance of an image performed by the microcomputer in the television according to the embodiment of the present invention;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Microcomputer 11 ... CPU 12 ... ROM 13 ... RAM 14 ... I / O 15 ... Operation panel 20 ... Tuner 21 ... Antenna 30 ... Chroma IC 31 ... Intermediate frequency amplification (VIF) circuit 32 ... Detection circuit 33 ... Synchronization circuit 34 ... Burst signal detector 35 PAL demodulator 36 SECAM demodulator 37 White balance adjuster 40 EEPROM 50 Picture tube discharge circuit 51 Cathode amplifier 52 Picture tube 53 Deflection circuit 54 Deflection coil 55 Fly Back transformer (FBT) 61 Audio amplifier 62 Speaker 100 Television

Claims (8)

[Utility model registration claims] 1. A tuner for inputting a television broadcasting signal according to the PAL system and the SECAM system to generate and output an intermediate frequency signal, and a tuner provided separately for the television and for displaying an image based on the television broadcasting signal of the PAL system. An EEPROM which stores a white balance adjustment value for adjusting a white balance and a SECAM black level adjustment value which is provided for each television and adjusts a black level of a video based on a SECAM television broadcast signal; A video signal is generated and output from the intermediate frequency signal input from the tuner based on the balance adjustment value so as to adjust the white balance of the video based on the television broadcast signal, and the SECAM black level adjustment value is When input, S
A video signal is created and output from the intermediate frequency signal so that the white balance of the video based on the white balance adjustment value is adjusted within a predetermined range in accordance with the SECAM television broadcast signal by the ECAM black level adjustment value. And a microcomputer having a ROM storing a program for controlling an internal circuit of the television, and a picture tube discharge circuit for displaying an image based on an image signal output from the chroma IC. The EEPROM stores a correction program created so as to correct a defect of the program stored in the ROM in the final adjustment step of the television. The microcomputer stores the program stored in the ROM and the EEPROM. The tuner and clock based on the patch stored in And the broadcast system of the television broadcast signal is determined. When the broadcast system is determined to be the PAL system, the white balance adjustment value is read from the EEPROM and the chroma IC is read.
, And when the above-mentioned SECAM method is determined, the white balance adjustment value and S
Read the ECAM black level adjustment value and read the chroma IC
In the correction program stored in the EEPROM, the correction program stored in the EEPROM is added to the white balance adjustment value to add a white balance adjustment value to the correction program stored in the EEPROM. The microcomputer includes a SECAM offset value that adjusts the balance for each television. When the microcomputer determines that the broadcasting system of the television broadcast signal is the SECAM system, the microcomputer performs the EEPRO.
M based on the correction program stored in M
The white balance adjustment value is corrected by adding the offset value for M to the white balance adjustment value, and the corrected white balance adjustment value is output to the chroma IC. The chroma IC is input from the microcomputer. Creating and outputting a video signal so as to adjust a white balance of a video based on the SECAM television broadcast signal from the intermediate frequency signal from the tuner based on the corrected white balance adjustment value. Television characterized by the following. 2. A tuner means for inputting a television signal according to a plurality of broadcasting systems to create and output an intermediate frequency signal, and a tuner means provided for each of the televisions and for outputting an image based on the television signal of the first broadcasting system. A non-volatile memory that stores a white balance adjustment value for adjusting a white balance and a second broadcast adjustment value that is provided for each television and adjusts an image based on a television signal of a second broadcast system; A video signal is created from the intermediate frequency signal input from the tuner means based on the white balance adjustment value to adjust a white balance of a video based on the television signal, and a video is displayed. When the second broadcast adjustment value is input, the video based on the same white balance adjustment value is used for the second broadcast adjustment value. Video display means for creating a video signal from the intermediate frequency signal and displaying a video so as to adjust the white balance within a predetermined range corresponding to the television signal of the second broadcast system; and When the broadcast system is determined, the white balance adjustment value is read from the same non-volatile memory and output to the image display means when the first broadcast system is determined, and when the second broadcast system is determined, The white balance adjustment value and the second broadcast adjustment value are read from the non-volatile memory, and the read white balance adjustment value is used to adjust the white balance of an image based on the second broadcast system television signal for each television. The corrected white balance adjustment value and the read second broadcast adjustment value are sent to the video display means. Television, characterized by comprising a white balance control means for force. 3. The nonvolatile memory stores a correction value for correcting the white balance adjustment value so as to adjust a white balance of an image based on the television signal of the second broadcast system for each television. The white balance control means reads the correction value from the non-volatile memory when determining the broadcast system of the television signal as the second broadcast system, and reads the white balance adjustment value. 3. The television according to claim 2, wherein the image is corrected and output to the video display means. 4. The correction value is an offset value that is added to the white balance adjustment value to adjust a white balance of a video based on the television signal of the second broadcast system for each television. The balance control means reads the offset value from the nonvolatile memory and adds the offset value to the white balance adjustment value when the broadcast method of the television signal is determined to be the second broadcast method. 4. The television according to claim 3, wherein the corrected white balance adjustment value is output to the video display means. 5. The television according to claim 2, wherein the nonvolatile memory is a memory capable of rewriting data to be stored. 6. The white balance control means has a ROM in which a program for controlling an internal circuit of the television is stored, and the rewritable nonvolatile memory stores the program stored in the ROM. A correction program created to correct a defect is stored, and the white balance control means is based on the television signal of the second broadcast system based on the correction program stored in the rewritable nonvolatile memory. 6. The television according to claim 5, wherein the white balance adjustment value is corrected so as to adjust the white balance of the video for each of the televisions, and output to the video display means. 7. The second broadcast adjustment value is a black level adjustment value that is provided for each television and adjusts a black level of an image based on a television signal of the second broadcast system. A television according to any one of claims 2 to 6. 8. The television signal of the first broadcasting system is a television signal of a PAL system, and the television signal of the second broadcasting system is a television signal of a SECAM system. A television according to any one of claims 2 to 7.