JPH0691673B2 - Color TV device for monitor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The following description will be given.

A Industrial Field B Outline of Invention C Conventional Technology D Problems to be Solved by the Invention E Means for Solving Problems (FIG. 1) F Action G Example (FIGS. 1 to 3) ) H Effect of Invention A Field of Industrial Application This invention relates to a monitor color television apparatus.

B Outline of the Invention The present invention is a color television apparatus for a monitor used in a television station or the like. When the white balance is automatically adjusted, the probe is calibrated to the outside light so that the white balance adjustment result is the outside light. It was designed so that it would not be affected by the above.

C Related Art A color television apparatus for a monitor used in a television station or the like requires high accuracy in color saturation, hue, white balance and the like. For this reason, in the past, a skilled technician manually performed the adjustment while looking at the color bar screen.

However, this method has various problems as a matter of course, and therefore, for example, Japanese Patent Application No. 60-77957 proposes a monitor television apparatus with automatic adjustment.

That is, when the color saturation and the hue are adjusted, the monitor television receiver to be adjusted is, for example, an EIA type color bar signal as shown in FIG. 5A or a full field type color bar signal as shown in FIG. 5B. A color bar signal is provided. The monitor television apparatus internally decodes (color demodulates) the three primary color signals from the color bar signal. Considering, for example, the blue signal B in the three primary color signals, the color bar signal is a full-field type. In this case (B in the same figure), the blue signal B is obtained in the periods T _{1 to} T ₄ of the bar containing blue as shown in C in the same figure.

Then, if the color saturation is adjusted correctly, the levels of the signals B in the periods T ₁ and T ₄ of the “white” bar and the “blue” bar of the color bar are equal to each other.

If the hue is adjusted correctly, the levels of the signals B of the color bars, for example, the “white” bar, the “cyan color” bar, and the “magenta” bar during the periods T ₁ , T ₂ , and T ₃ are Equal to each other.

Therefore, if the level (color gain) of the carrier color signal is controlled so that the levels of the signal B become equal to each other in the periods T ₁ and T ₄ , it means that the color saturation is properly adjusted.
If the phases (color hue) of the color subcarriers at the time of color demodulation are controlled so that the levels of the signals B of T ₁ , T ₂ and T ₃ are equal to each other, the hues are correctly adjusted.

Further, the automatic white balance adjustment is performed as follows. That is, first, a uniform red color is reproduced on the picture tube at a low brightness (for example, a signal level of 10 to 20 IRE), the brightness of the picture tube at this time is measured by a sensor, and this measurement value is prepared in advance. Compare with the standard color temperature value. Then, the gain and bias of the drive circuit of the picture tube are controlled until this measured value matches the reference value.

Then, a uniform red color with high brightness (for example, 100IRE
Signal level) and the luminance of the picture tube at this time is measured by a sensor, and the gain and bias of the drive circuit are controlled until the measured value matches the reference value.

Then, thereafter, similar control is performed for green and blue. Therefore, the white balance of the picture tube is set to the color temperature corresponding to the reference value prepared in advance.

D The problem to be solved by the invention However, when the white balance is adjusted as described above, if there is external light, this external light is superimposed on the light emission of the picture tube, and this is measured by the sensor. This measurement data becomes data brighter than the actual brightness of the picture tube. Therefore, if the white balance is adjusted while the external light is incident, an error due to the external light will occur in the white balance. In particular, when the luminance is low, the external light occupies a large proportion of the incident light of the sensor, so that the error of the white balance becomes large at the low luminance.

Therefore, in practice, the sensor is housed inside a relatively large suction cup type probe (30) as shown in FIG. 4A to block external light. However, this is not always sufficient, since external light may reach the sensor through the screen glass of the picture tube.

The sensor is, for example, a photovoltaic type photodiode, but the output current of this sensor is as small as 0.55 μA at 100 lux. Therefore, it is necessary to amplify the output of the sensor with a large gain, and the offset and drift of the amplifier for amplification become a problem.

In such a case, it is common to use that amplifier as a chopper amplifier to prevent offset and drift, but that would complicate the circuit.

The present invention is intended to solve the above problems.

E Means for Solving the Problems For this reason, in the present invention, the correction data of the sensor for the external light is obtained when the white balance is adjusted, and the measurement data is corrected by this correction data.

The F action measurement data is corrected by the correction data, and the white balance is adjusted by the true measurement data.

G Embodiment In FIG. 1, (1) to (9) are signal systems of color video signals. Then, in general use, the composite color video signal is supplied from the input terminal (1) to the separation circuit (3) through the switch circuit (2) to be separated into the luminance signal Y and the carrier color signal C. Is supplied to the matrix circuit (4), and the signal C is supplied to the color demodulation circuit (6) through the gain control amplifier (5) to generate red, green,
Blue color difference signals (RY), (GY), and (BY) are demodulated, and these signals (RY) to (BY) are supplied to the matrix circuit (4). Thus, from the matrix circuit (4), the signal Y and the signals (RY) to (B-
Y), the three primary color signals R, G, B of red, green, and blue are taken out, and these signals R to B are colored through the brightness and contrast adjustment circuit (7) and further through the drive circuit (8). It is supplied to the picture tube (9) and the color image is reproduced on the picture tube (9).

Further, (11) to (19) are microcomputers for performing the above-described automatic adjustment, (11) is a CPU for the 8-bit parallel processing, and (12) is a program and data for the automatic adjustment. The ROM (13) is a RAM for the work area and the RAM for the data area. The ROM (12) is shown in FIG. 2 and FIG.
The routines (50) and (100) shown in the figure are written. The memories (12) and (13) are connected to the CPU (11) through the system bus (19), and the keyboard (14) for inputting the mode or item of automatic adjustment is connected to the port (15). Connected to the path (19) through. The RAM (13) is composed of, for example, a C-MOS, and is backed up by a battery (16).

Further, (21) is a D / A converter and (22) is an output port. The converter (21) converts the data from the CPU (11) into an analog signal, and the analog signal is converted into the circuits (5) to (8). As its control signal,
The switch circuit (2) and the drive circuit (8) are controlled by the CPU (11) through the port (22). further,
(23) is a character generator, which is a CPU (11)
The person adjusting this monitor television device forms a character signal of a sentence that indicates what should be done next, and the character signal is transmitted through the switch circuit (2) to the separation circuit (3). It will be supplied later. Therefore, when adjusting this monitor television device, each adjustment can be performed interactively according to the instruction displayed on the screen of the picture tube (9).

Further, (24) is a forming circuit for forming a video signal for white balance adjustment, which is controlled by the output signal of the D / A converter (21) and has a video signal of light luminance (for example, 100IRE) and a low luminance (100IRE). Video signals of, for example, 10 to 20 IRE) are selectively formed. Then, the formed video signal is supplied to the subsequent circuit through the switch circuit (2).

Further, (25) is a switch circuit to which, for example, a blue signal B from the adjusting circuit (7) and a signal from a probe (30) described later are supplied, and these signals are supplied to the port (2
Select and take out according to the output of 2). Also, (26) is a sampling and holding circuit, which is a switch circuit (25).
Is sampled and held, and the control signal for sampling and holding is formed in the forming circuit (27) in synchronization with horizontal and vertical scanning. Further, (28) is an A / D converter for A / D converting the sampling and holding outputs, and the converter output is taken into the CPU (11) through the bus (19).

Further, (30) is a probe used for adjusting the white balance, which includes a photo sensor (31) for receiving light from the picture tube (9), a shaping amplifier (32) for the output, and a non-volatile memory ( 33) and the whole is of a suction cup type as shown in FIG. The output of the amplifier (32) is supplied to the switch circuit (25) through the plug (34) and the jack (44), and the memory (33) is
It is connected to the bus (19) through the plug (34), the jack (44) and the port (43). In this case the memory (33)
Is an electrically erasable and writable P-ROM, that is, EEPROM (registered trademark), for storing four sets of white balance data, that is, color temperature data. The first of the four sets of data
Data of a predetermined color temperature is stored by the manufacturer at the time of shipment from the factory. Further, the data access of the memory (33) is performed serially.

It should be noted that in FIG. 4, the keyboard (14) is of a pull-out type, and is in a pulled-out state in this figure. Further, in FIG. 9B, (100) is a reference color temperature monitor television device.

Then, the color saturation and the hue are adjusted by the following operations and actions.

That is, in this case, the color bar signal is supplied to the terminal (1). The probe (30) is not used. Then, the saturation and hue adjustment are designated by the keys (switches) of the keyboard (14).

Then CP based on the keystrokes on this keyboard (14)
The switch circuit (2) is connected to the contact on the side of the character generator (23) by the U (11), and the CPU (1
A control signal is supplied from 1) to the character generator (23) and a predetermined character signal is extracted from the character generator (23), which is supplied to the switch circuit (2) and input to the picture tube (9). A text is displayed asking whether the color bar signal being displayed is of the EIA type as shown in FIG. 5A or of the full field type as shown in FIG. 5B.

Therefore, if the input color bar signal is, for example, of the full field type (B in the figure), it is input from the keyboard (14).

Then, the switch circuit (2) is connected to the terminal (1) as shown in the figure.
The color bar signal of the terminal (1) is supplied to the subsequent stage through the switch circuit (2).
The switch circuit (25) is connected to the contact on the adjusting circuit (7) side as shown in the figure, and the blue signal B from the adjusting circuit (7), that is, the blue signal B in the color bar signal is held by the sampling and holding circuit (26). Is supplied to. In this case, since the color bar is of the full-field type shown in FIG. 5B, the blue signal B supplied to the sampling and holding circuit (26) is in the periods T _{1 to} T ₄ as shown in FIG. 5C. You get each.

And, if the color saturation is adjusted correctly, the duration of the color bars, for example "white" and "blue" bars.
The levels of the signals B of T ₁ and T ₄ are equal to each other. In addition, if the hue is adjusted correctly, the period of the bar of "white", "cyan" and "magenta" of the color bar
The levels of the signals B of T ₁ , T ₂ and T ₃ are equal to each other.

Therefore, first, the color saturation is adjusted. That is,
In the sampling and holding circuit (26), the signal B in the white period T ₁ of a predetermined horizontal line is sampled and held by the control signal from the forming circuit (27), and this output level is digitalized by the A / D converter (28). The data, which is data and indicates the level of the signal B in the period T ₁ , is stored in the RAM (13).

Subsequently, similarly, data indicating the level of the signal B in the blue period T ₄ is stored in the RAM (13), and then these periods T ₁ ,
When the data indicating the level of T ₄ are compared and when the levels are different, a gain control signal is supplied from the CPU (11) to the amplifier (5) through the D / A converter (21), and the amplifier (5) is supplied.
The gain of is changed by one step and thus the color saturation is changed by one step.

Next, similarly, data indicating the level of the signal B in the blue period T ₄ is stored again in the RAM (13), and this is compared with the data indicating the level of the white period T ₁ that was stored first. , Furthermore, the gain of the amplifier (5) is changed by one step.

Then, such an operation is performed until the level of the signal B in the period T ₂ becomes equal to the level of the signal B in the period T ₄ , and when both levels become equal, the color saturation is properly adjusted. After that, the adjustment of the color saturation is completed.

Then, the processing of the CPU (11) next enters the adjustment of hue. In this hue adjustment, the signal B in the periods T ₁ , T ₂ , T ₃
Level is detected, the data is stored in the RAM (13), and each level is compared with the level of the period T ₁ as a reference. When the levels are different, the CPU (11) outputs D / A
A control signal is supplied to the color demodulation circuit (6) through the converter (21) to change the phase of the color subcarrier used for color demodulation by one step, and thus the hue is changed to one.
Only steps are changed.

Then, such an operation is performed until the level of the signal B in the period T ₁ and the level of the signal B in the periods T ₂ and T ₃ become equal, and when both levels become equal, the hue is properly adjusted. After that, the hue adjustment is completed.

Next, in this example, the adjustment circuit is used so that the level of the signal B in the period T ₁ and the period of the color bar “black” bar coincides with the data written in the ROM (12) as a reference. In (7), the DC gain and the AC gain are controlled to adjust the brightness and contrast to the reference state.

When all the above adjustments are completed, the switch circuit (2) is connected to the contact on the side of the character generator (23), and the character generator (23) is controlled to complete the adjustment of the picture tube (9). A sentence indicating that is displayed.

Then, when this display is performed for a certain period, the switch circuit (2) is connected to the contact on the side of the terminal (1) and switched to the normal mode (general use state).

When the above adjustment is completed, the RAM (13) has the final data of the level of the signal B in the periods T _{1 to} T ₅ and the period of the “black” bar of the color bar. .
That is, the RAM (13) retains the data when the color saturation and hue have been adjusted correctly.

On the other hand, the white balance is adjusted by the CPU (11) executing the routines (50) and (100).

That is, in this case, the probe (30) is prepared and its plug (34) is connected to the jack (44). And
Use the keys on the keyboard (14) to specify the white balance adjustment.

Then, the processing of the CPU (11) starts from step (51) of the routine (50), and in the next step (52), a character signal is output from the character generator (23), and this signal is output to the switch circuit (2). Then, a picture is displayed on the picture tube (9) asking whether to adjust the white balance to the already stored color temperature or to newly store the color temperature.

Then, if the white balance is to be adjusted to the stored color temperature, this is input from the keyboard (14).

Then, this key input is determined in step (53), and the process proceeds from step (53) to step (54),
In the picture tube (9), a sentence indicating which group in the memory (33) the color temperature stored in this step (54) belongs to is displayed.

Therefore, if this is the first set of color temperatures (factory-shipped data), this is designated by the keyboard (14).

Then, the process proceeds from step (54) to step (55), the color temperature data of the first set is serially taken out from the memory (33), and is transferred to the RAM (13) through the port (43).
Then, the window is displayed on the picture tube (9) by the output signal of the character generator (23) in step (56), and the probe (30) is attracted to this window portion. Is displayed.

Then, as shown in FIG. 4A, the probe (30) is adsorbed to the window and this is input from the keyboard (14).

Then, the process proceeds to step (57), the drive circuit (8) is controlled to cut off all the signal systems of the signals R to B, the picture tube (9) is brought into a non-luminous state, and then the step (58). ), The switch circuit (25) is connected in the state opposite to the one shown in the figure, and the output signal of the sensor (31) becomes the amplifier (32).
And a sampling and holding circuit (26) through a switch circuit (25) to extract a signal at a predetermined time point, that is, a predetermined display position of the picture tube (9), and the signal is output by an A / D converter (28). Digitized RAM (1
Stored in 3). In this case, since all signal systems of the picture tube (9) are cut off, the data taken into the CPU (11) shows the level of external light leaked into the sensor (31) from the outside. Will be there. That is,
The external light incident on the sensor (31) is measured at this step (58).

Subsequently, the process proceeds to step (59), in which the memory (33) is stored in step (55).
From the reference data transferred from the RAM (13) to the step (5
The external light data measured in 8) is added. Therefore, the reference data of the RAM (13) becomes bright data by the amount of outside light.

Next, the process proceeds to step (61), and the switch circuit (2)
Is connected to the contacts on the forming circuit (24) side, and the CPU
Based on the output of (11), a low-luminance video signal is output from the forming circuit (24), and this signal is output to the switch circuit (2).
Is supplied to the circuit in the subsequent stage through. Also, CPU (1
By 1), the signal system of the green signal G and the blue signal B of the drive circuit (8) is cut off. Therefore, the picture tube (9) has a low brightness and is uniformly colored in red.

Then, in step (62), the red light is
The photo sensor (31) of the probe (30) receives the light, and the amplifier (32) outputs a signal of a level corresponding to the amount of emitted red light (including external light). At this time, the switch circuit The signal from the amplifier (32) is connected to the switch path (2
A signal indicating the amount of red light at a predetermined time point, that is, a predetermined display position of the picture tube (9) is supplied to the sampling and holding circuit (26) through 5), and this signal is extracted from the A / D converter (28). ) Digitized by RAM (1
Stored in 3) and then in step (63) the red light data of step (62) is compared with the corresponding data transferred from memory (33) to RAM (13) in step (55). . In this case, since the external light data is added to the reference data in step (58) in step (59), even if the red light measured in step (62) includes external light, In 63), the reference data will be compared with the true red light measurement data.

And as a result of this comparison, when both data are different,
The process proceeds to step (64), where the bias and gain of the drive circuit (8) for the red signal R is changed by one step from the CPU (11) through the D / A converter (21). The amount of red light emitted is changed by one step.

Then, after this change, the process returns to step (62), and thereafter, the operations of steps (62) to (64) are repeated until both data to be compared become equal.

Then, when both data become equal (within the permissible error), the process proceeds from step (63) to step (65), a high-luminance video signal is output from the forming circuit (24), and the step (61) is performed. .. (64), the bias and the gain are changed for the high-intensity red signal R. Thus, the red light has a light emission characteristic corresponding to the data transferred from the memory (33) to the RAM (13), in this case, the data at the time of factory shipment.

Then, thereafter, in steps (71) and (72), the same processing is performed on the green light and the blue light, and the light emission characteristics corresponding to the factory-shipped data are obtained. Therefore, the white balance is adjusted to the color temperature corresponding to the factory-shipped data.

Then, when this adjustment is completed, in step (73), a text signal from the character generator (23) displays a sentence indicating that the white balance adjustment is completed, for example, on the upper part of the picture tube (9) for a certain period. After that, the normal mode is returned by step (74).

When the white balance adjustment is completed, the RAM (13) has data for obtaining the white balance.

Furthermore, the color temperature of the picture tube (9), that is, the RAM (13)
When the color temperature data of is newly stored in the memory (33), for the text displayed in step (52),
Input that it is a memory of color temperature with the keyboard (14).

Then, this is discriminated by the step (53), and the processing advances to the step (81), where the character generator (23)
The picture signal from the picture tube (9) causes the memory (37)
A text is displayed asking how many sets of new data are to be stored. For example, if it is the second set, when this is input from the keyboard (14), the probe (30 ) The text and the window prompting the adsorption of are displayed.

Then, according to this display, the probe (30) is adsorbed as shown in FIG. 4A, and this is done by the keyboard (14).
Enter from.

Then, the process proceeds to step (83), the drive circuit (8) is controlled so that the signal systems of the signals R to B are all cut off, the picture tube (9) is in the non-light emitting state, and then the step ( In 84), the switch circuit (25) is connected in the state opposite to the one shown in the figure, and the output signal of the sensor (31) becomes the amplifier (3
2) and the switch circuit (25) and is supplied to the sampling and holding circuit (26) to take out a signal at a predetermined time point, that is, a predetermined display position of the picture tube (9), and this signal is A / D converter RAM digitized by (28)
Stored in (13). Therefore, this step (8
In 4), the external light incident on the sensor (31) is measured.

Subsequently, the process proceeds to step (85), where a low luminance video signal is formed in the forming circuit (24) and the signal is supplied to the subsequent stage through the switch circuit (2).
Green signal G and blue signal B in the drive circuit (8)
The signal system of is cut off, so that the picture tube (9) emits red light uniformly with low luminance.

Then, in step (86), the red light is received by the probe (30), and data indicating the light amount of the red light (including external light) is extracted from the converter (28) in the same manner as above. This measurement data is written in the RAM (13).

When this writing is completed, in step (87), the video signal from the forming circuit (24) is made a high-luminance signal in the same manner as in steps (85) and (86), and therefore the picture tube (9) is , With high brightness and uniform red emission. Then, the data indicating the light amount of the red light is similarly written in the memory (33).

Further, also for green and blue light, data at low brightness and at high brightness are similarly extracted and written in the memory (33).

Then, when the above process is completed, in step (93), the RAM (1) measured in steps (86) to (92) is measured.
Step (84) from each color light data stored in 3)
The measurement data of the external light measured by is subtracted to obtain the true measurement data of each color light.

Then, in step (94), the corrected data is supplied to the memory (33) through the port (43) and written in the address of the second set designated in step (81). The end of the process is displayed in step (95), and then the normal mode is returned to in step (96). Therefore, at this time, new data of the color temperature is written in the memory (33).

When the color temperature data of another monitor television device is stored in the memory (33), as shown in FIG. 4B, the master monitor television device (100) is prepared and the connector (45) is used. Signal RB from the above) is supplied to the device (100) through the cable (110). The probe (30) is adsorbed on the picture tube (109) of the device (100).

Then, in step (83), the levels of the signals R to B output to the connector (45) are set to a cutoff level (for example, -5IRE), and the device (100) correspondingly corresponds to each color light emission. The drive circuit of is switched to emit red light, green light, and blue light. Therefore, in this case, the color temperature data of the device (100) can be written in the memory (33).

As described above, the RAM (13) retains the adjusted data such as the color saturation, the hue and the white balance as they are, and the data is backed up by the battery (16) even when the power is turned off. Then, when the power is turned on next time, the circuit (5) is generated by the data remaining in the RAM (13).
(8) are set, and therefore, the color saturation, hue, white balance, etc. are those at the time of the previous adjustment.

As described above, according to this monitor television device, the color saturation, hue, white balance, etc. are automatically adjusted.

Then, in this case, particularly according to the present invention, the external light leaking to the sensor (31) of the probe (30) is measured,
Since the data for each color light is corrected by the measurement data of the outside light, the data of the correct color light can be obtained and the white balance can be adjusted correctly regardless of the outside light.

Furthermore, since the outside light is measured and corrected immediately before measuring the level of the colored light, the offset and drift of the amplifier (32) are also regarded as outside light and are corrected. Therefore, the amplifier (32) is simple. It can be anything.

The routine (100) of FIG. 3 includes steps (58) and (84).
The details of measuring external light are shown in.

That is, this routine (100) starts from step (101), and in step (101), the ambient light is reduced to, for example, 1
The measurement is performed 6 times, then in step (102), the difference between the maximum value and the minimum value of the 16 measurement data is obtained, and in step (104), it is checked whether the difference is within the allowable value. . That is, when adjusting the white balance, the data of each color light is corrected by the data of the external light, but when the external light fluctuates significantly, the measurement of the external light and the measurement of each color light are performed. However, the amount of outside light is different, and as a result, correct correction cannot be performed. Therefore, the step (104) is to check the fluctuation of the outside light.

Then, when the difference obtained in step (103) is less than or equal to the allowable value, the fluctuation of external light is small, and therefore there is no problem in correcting the color light data with the external light data measured in step (101). Assuming that the process proceeds from step (104) to step (105), the average value of 16 measurement data is obtained, and then the average value is stored in the RAM (13) as the external light measurement data in step (106). Then, this routine (100) is ended by the step (107).

If the difference obtained in step (103) exceeds the allowable value in step (104), it is considered that there is an error in correcting the data of each color light with the data of the external light because the fluctuation of the external light is large. Is from step (104) to step (1
Proceed to step 11) and display on the picture tube (9) that the white balance cannot be adjusted by outside light by the character signal from the character generator (23).
Return to 2).

Therefore, according to this routine (100), correct external light data can be obtained.

H Effect of the Invention According to the present invention, the external light leaking to the sensor (31) of the probe (30) is measured, and the data for each color light is corrected by the measured data of the external light. Regardless of the light, correct color light data can be obtained and the white balance can be adjusted correctly.

Furthermore, since the outside light is measured and corrected immediately before measuring the level of the colored light, the offset and drift of the amplifier (32) are also regarded as outside light and are corrected. Therefore, the amplifier (32) is simple. It can be anything.

[Brief description of drawings]

FIG. 1 is a system diagram of an example of the present invention, and FIGS. 2 to 5 are diagrams for explaining the same. (1) to (9) are signal systems, (11) to (19) are microcomputers,
(30) is a probe.

Claims (1)

[Claims] 1. A sensor for measuring the quantity of light from a picture tube, and a memory for storing the level of the quantity of light measured by the sensor. The picture tube is put into a non-luminous state, and at the same time, the sensor The reference data, which is the reference of the white balance, is corrected by the measurement data, and the picture tube is made to emit light, and the measurement data of the sensor at this time is adjusted so that the measurement data of the sensor becomes equal to the corrected reference data. A color TV device for monitors that adjusts the white balance.