JPH0691672B2 - Luminance sensor probe - Google Patents

Description

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

A Industrial field of use B Outline of the 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 and 2) ) H Effect of Invention A Field of Industrial Application This invention relates to a brightness sensor probe.

B Outline of the Invention The present invention is to increase the response speed by integrating the sensor output of a probe for measuring the brightness of a picture tube and resetting the integrated value at a predetermined timing.

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.

FIG. 3 shows an example thereof, and (1) to (9) are color video signal systems. 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) and the red, green and blue color difference signals (RY) and (GY). , (B-
Y) is demodulated, and the signals (RY) to (BY) are supplied to the matrix circuit (4). Thus, from the matrix circuit (4), the signal Y and the signal (RY) to
(BY), three primary color signals R, G, B of red, green, and blue are taken out, and these signals R to B are passed through the brightness and contrast adjusting circuit (7) and further to the drive circuit (8 )
Supplied to the color picture tube (9) through the picture tube (9)
The color image is played back.

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. ROM (13) is a RAM for work area and RAM for data area. These memories (12) and (13) are connected to the CPU (1
In addition to being connected to 1), a keyboard (14) for inputting an automatic adjustment mode or item is connected to a bus (19) through a port (15). RA
The M (13) is composed of, for example, a C-MOS, and has a battery (16).
Has been backed up by.

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 a D / A converter (21).
Controlled by the output signal of 1) to selectively form a high-luminance (for example, 101IRE) video signal and a low-luminance (for example, 10 to 20IRE) video signal. 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 monitor television device having a reference color temperature.

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. Also, if the hue is adjusted correctly, the duration of the bar of, for example, "white", "cyan" and "magenta" in 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 the output level is set by the A / D converter (28). Data that is digital data and indicates the level of the signal B during this period T ₁ is stored in the RAM (13).

Subsequently, similarly, data indicating the signal level of the blue period T ₄ is stored in the RAM (13), and then these periods T ₁ , T ₄ are stored.
When the data indicating the levels are compared and 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 gain of the amplifier (5) is only one step. Is changed, 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 ₁ 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, so that the hue is 1
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.

Subsequently, in this example, the data written in the ROM (12) is used as a reference, and the level of the signal B during the period T ₁ and the period of the “black” bar of the color bar is adjusted to be the same. In the circuit (7), the DC gain and 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 a signal B in the periods T _{1 to} T ₅ and the “black” bar of the color bar.
The final data of the level will remain. That is, the RAM (13) retains the data when the color saturation and hue have been adjusted correctly.

On the other hand, white balance is performed by the following operations and actions.

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, a character signal is output from the character generator (23), and this signal is supplied to the subsequent stage through the switch circuit (2), and whether the white balance is adjusted to the color temperature already stored in the picture tube (9). A sentence asking if you want to remember the color temperature is displayed.

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

Then, a sentence asking which set of the memory (33) the stored color temperature belongs to is displayed on the picture tube (9).

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

Then, the color temperature data of the first set is serially taken out from the memory (33), and the RAM (1
3) Transferred to and stored. Further, a window is displayed on the picture tube (9) by the output signal of the character generator (23), and a sentence to adsorb the probe (30) is displayed on the window portion.

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

Then, the switch circuit (2) is connected to the contact on the forming circuit (24) side, and a low-luminance video signal is output from the forming circuit (24) based on the output of the CPU (11). It is supplied to the subsequent circuit through the switch circuit (2). Further, the signal system of the green signal G and the blue signal B of the drive circuit (8) is cut off by the CPU (11). Therefore, the picture tube (9) has a low brightness and is uniformly colored in red.

Then, the red light is received by the photo sensor (31) of the probe (30), and a signal of a level corresponding to the light amount of the red light is extracted from the amplifier (32). At this time, the switch circuit (25 ) Is connected to the contact opposite to that shown in the figure, and the signal from the amplifier (32) is supplied to the sampling and holding circuit (26) through the switch circuit (25) at a predetermined time, that is, a predetermined time of the picture tube (9). The signal at the display position of is taken out, and this signal is digitized by the A / D converter (28) and taken into the CPU (11). Then, the data indicating the red light emission amount at the time of the low brightness is stored in the RAM (13) and is compared with the corresponding data transferred from the memory (33) to the RAM (13), and both data are stored. When different, the bias and the gain of the drive circuit (8) for the red signal R are changed by one step from the CPU (11) through the D / A converter (21), so that the red light emission amount of the picture tube (9) is changed. Only one step is changed.

Then, the light emission amount after the change is detected in the same manner, the data is stored in the RAM (13), and the memory (3
It is compared with the data transferred from 3), and when different, the bias and gain for the red signal R of the drive circuit (8) are changed by one step again.

Then, such an operation is repeated until the compared quantity data become equal.

Then, when both data become equal, the formation circuit (2
From 4), a high-luminance video signal is output, and thereafter, the bias and gain of the high-luminance red signal R are similarly changed. Thus, the red light is RA from the memory (33).
The light emission characteristics correspond to the data transferred to M (13), which is the data at the time of factory shipment in this case.

After that, similar processing is performed on the green light and the blue light, and the emission characteristics corresponding to the data at the time of factory shipment are obtained. Therefore, the white balance is adjusted to the color temperature corresponding to the factory-shipped data.

When this adjustment is completed, a text signal from the character generator (23) causes a text indicating that the white balance adjustment is completed, for example, to be displayed on the upper part of the picture tube (9) for a certain period of time. Return to mode.

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 new color temperature data is stored in the memory (33), the keyboard (1
Input by 4).

Then, the character signal from the character generator (23) causes the picture tube (9) to display a text asking how many sets of the memory (37) should store the new data. Then, when this is input from the keyboard (14), a sentence and a window prompting the adsorption of the probe (30) are displayed next.

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, a low-luminance video signal is formed in the forming circuit (24), this signal is supplied to the subsequent stage through the switch circuit (2), and the signal system of the green signal G and the blue signal B in the drive circuit (8). Is cut off, so that the picture tube (9) emits red light uniformly with low brightness.

Then, this red light is received by the probe (30),
Similar to the above, data indicating the amount of red light is output from the converter (28). Then, this data is supplied to the memory (33) through the port (43), and is written to the first designated address of the second set.

Then, when this writing is completed, the video signal from the forming circuit (24) is made a high-luminance signal, and therefore, the picture tube (9) is made to uniformly emit red light with high luminance. 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).

By the above processing, the data regarding the color temperature of the picture tube (9) is written in the address of the second set of the memory (33), and the end of the processing is displayed and then the normal mode is returned to. 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, the device (10
The drive circuit of 0) is switched to emit red light, green light, and blue light. Therefore, in this case, the device (10
The color temperature data of 0) 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.

By the way, the above-mentioned probe (30) is generally constructed as shown in FIG.

That is, the photo sensor (31) is, for example, of a photovoltaic type, the output of which is supplied to the operational amplifier (321), and the operational amplifier (321) is connected to an integrating capacitor Ca and a resistor Ra. Shaping amplifier (32)
Is composed of a Miller integrating circuit.

Therefore, when adjusting the white balance, the probe (3
When (0) is adsorbed to the picture tube (9), as shown in FIG. 7A, a pulse Pa of a level corresponding to the brightness of the picture tube (9) is distributed from the sensor (31) in a substantially normal distribution in the field period. , And is obtained in a horizontal cycle within that group. Then, this pulse Pa is supplied to the integrating circuit (32).
As shown in FIG. 7B (dashed line indicates pulse
The envelope of Pa is shown), and the DC voltage Eb is at a level corresponding to the brightness of the picture tube (9), and this voltage Eb is taken out from the plug (34) as the output of the probe (30).

Therefore, the white balance can be adjusted as described above based on the detected voltage Eb.

D Problem to be solved by the invention However, in the probe (30) described above, the detection voltage is
If the ripple of Eb is large, this appears as a luminance detection error.Therefore, the ripple of the voltage Eb needs to be small. For this purpose, the time constant of the elements Ca and Ra must be increased to several seconds. There is.

However, if this time constant is large, the response of the change of the voltage Eb to the change of the brightness becomes slow, and therefore the time required for adjusting the white balance becomes long.

In addition, the pulse Pa is peak-held to detect the luminance detection voltage Eb.
However, in this case, when the distance from the picture tube (9) to the sensor (31) shifts when the probe (30) is adsorbed, as shown by the broken line in FIG.
Since the level of Pa becomes small, this becomes a detection error. In the case of peak hold, the sensor (3
Since the dot that gives the highest brightness to 1) is effective, the voltage Eb will fluctuate due to the position of the sensor (31) and dust adhering to the screen surface of the picture tube (9), resulting in low accuracy. Will end up.

The present invention seeks to further overcome these problems.

E Means for Solving the Problems For this reason, in the present invention, the output of the sensor (31) is integrated with a large time constant, and the integrated value is reset at a predetermined timing.

F action The luminance is detected without being affected by the ripple component and the response speed is increased.

G Embodiment In FIG. 1, the photosensor (31) is, for example, of a photovoltaic type, and its output is supplied to an operational amplifier (321), and this operational amplifier (321) has a capacitor C ₁ for integration. And the resistor R ₁ are connected to form a Miller integrating circuit. However, this integrator circuit is mainly intended for noise removal, and therefore the time constants of the elements C ₁ and R ₁ are reduced to a few milliseconds or less, and the capacitor C ₁ may be omitted in some cases. .

The output of the amplifier (321) is supplied to a operational amplifier (322) through a resistor R _2, a capacitor C ₂ is connected Miller integrating circuit for integrating the operational amplifier (322) is constructed and its The output is taken out to the plug (34).

Further, the switch circuit (323) is connected in parallel to the capacitor C _2, and the vertical synchronizing pulse Pv is supplied to the switch circuit (323) as a control signal through the plug (34), so that the switch circuit (323) is in the period of the pulse Pv. Is turned on. The sampling and holding circuit (26) performs sampling and holding immediately before the vertical synchronizing pulse Pv.

With this configuration, when adjusting the white balance,
From the sensor (31), as shown in FIG.
(Same as Figure A), pulse Pa is obtained, and this is the amplifier (32
It is supplied to the amplifier (322) through 1) and integrated. At this time, since only the capacitor C ₂ is connected for integration in the amplifier (322), its time constant is very large. Therefore, as shown in FIG. , That is, the brightness detection voltage Eb
Is a DC voltage with no ripple.

However, in the vertical blanking period, the switch circuit (323) is activated by the vertical synchronizing pulse Pb as shown in FIG.
Is turned on and the voltage Eb is reset.

Therefore, the voltage Eb from the operational amplifier (322) is
The waveform is as shown in, but this voltage Eb is
4) is supplied from the switch circuit (25) to the sampling and holding circuit (26), is sampled and held immediately before the pulse Pv, and then is converted to the converter (2
It is taken into CPU (11) through 8).

Thus, according to the present invention, the luminance detection voltage Eb is taken out from the probe (30). In this case, in particular, according to the present invention, the detection voltage Eb is reset by the vertical synchronizing pulse Pv. Therefore, the voltage Eb responds to the change in luminance within one field period, and the response speed is fast. Therefore, the white balance can be adjusted in a short time.

Moreover, since the time constant can be made sufficiently large with respect to the voltage Eb, the ripple component is not included, and the luminance can be accurately measured.

Further, even if the distance from the picture tube (9) to the sensor (31) is shifted and the level of the pulse Pa is reduced as shown by the broken line in FIG. 2A, the pulse Pa is integrated to obtain the voltage Eb. Therefore, the fluctuation of the voltage Eb is small, and therefore the luminance detection error is small.

Also, since the pulse E is integrated to obtain the voltage Eb, this means that all the brightness in a certain area of the screen surface of the picture tube (9) is to be seen, and this is attached to the position of the sensor (31) and the screen surface. The influence of dust and the like is reduced and the detection voltage becomes close to that of human vision.

[Brief description of drawings]

FIG. 1 is a system diagram of an example of the present invention, and FIGS. 2 to 7 are diagrams for explaining the same. (31) is a photo sensor, and (321) and (322) are operational amplifiers.

Claims (1)

[Claims] 1. A photosensor provided on the front surface of a picture tube for outputting a signal indicating its brightness, an integrating circuit for integrating an output signal of the photosensor, and a switch circuit for resetting an integrated output of the integrating circuit. And a luminance sensor probe having the switch circuit controlled at a predetermined cycle to reset and take out the integrated output at the predetermined cycle.