JPH0142555B2 - - Google Patents

Description

[Detailed Description of the Invention] In a multi-tube color television camera, the scanning area of the electron beam for the subject image projected on the photoelectric conversion surface may vary depending on the image pickup tube. As shown in Figure 1 A to F
There is something like this.

That is, in FIGS. 1A to 1F, Ag indicates a scanning area of an electron beam with respect to a subject image in a reference image pickup tube for, for example, green color, and Ar indicates a similar scanning area in, for example, a red image pickup tube. And, Fig. 1A shows the area Ar for the area Ag.
If the position of the area is shifted in the vertical direction, Figure 1B shows that the vertical size of the area Ar is shifted with respect to the area Ag, and Figure 1C shows that the area Ar is uniform in the vertical direction with respect to the area Ag. This is the case when the slope is inclined at a ratio of . Moreover, FIGS. 1D to 1F are cases in which there is a shift in the horizontal direction in the same way as in FIGS. 1A to C.

If the scanning area of the electron beam is shifted for each image pickup tube in this way, color shift will occur on the reproduced screen. Therefore, in a multi-tube type camera, it is necessary to precisely match the scanning area of the electron beam, that is, to adjust the registration.

The present invention allows such registration adjustment to be made easily and accurately.

An example of this will be explained below. In this example, the camera is a three-tube type, and the electron beam scanning area Ag of the green image pickup tube for the subject image is used as a reference, and the electron beam scanning area of the other image pickup tubes is This is a case where registration adjustment is performed. In addition, there are six types of adjustment targets for each image pickup tube shown in FIGS. 1 A to F, and these are numbered [1] to [6] shown in FIGS. 1 A to F.
shall be carried out in the following order.

In Figure 2, 1G, 1R, 1B are for green;
Image pickup tubes for red and blue; 2G, 2R, 2B and 3G, 3R, 3B are their vertical and horizontal deflection plates (or deflection coils); 4 is a vertical deflection circuit; 5 is a horizontal deflection circuit; , 5 are supplied to the deflection plates 2G, 3G, and are also supplied to the deflection plates 2R, 3R via adder circuits 51, 52.

Further, 30 indicates a sequence controller,
This entire circuit is controlled by this controller 30. According to the control signal from the controller 30, the switch circuit 21 is connected to the state shown in the figure when adjusting the image pickup tube 1R, and is connected to the state shown in the figure when adjusting the image pickup tube 1B. In addition, the switch circuit 15 is connected to the state of
When adjusting in the horizontal direction (D to F in FIG. 1), it is connected in the state shown in the figure, and in the opposite state from that shown in the figure when adjusting in the horizontal direction (D to F in FIG. 1).
Furthermore, enable signals, clocks, address signals, read/write signals, control signals, etc. are also taken out from the controller 30 and supplied to the respective circuits.

And from the image pickup tubes 1G, 1R, and 1B, green,
Red and blue color signals G, R, and B are taken out, but in this case, a DC bias voltage is supplied to the deflection plates 2G and 3G, and the scanning position of the electron beam of the image pickup tube 1G is adjusted by one scanning line. It is shifted vertically (downward as seen from the subject image) and horizontally (rightward as seen from the subject image) by 1/2 pixel, and the green signal G is (1H+τ) more than the original point.
(1H is one horizontal period, τ is 1/2 pixel period) and is taken out at a point in time (phase).

In this case, the reason why the delay period includes the period τ is to perform image enhancement (a kind of aperture control) using the green signal G.

This signal G is then supplied to the delay circuit 11 to become _a signal _G1 delayed by one horizontal period as shown in FIGS. As _shown in FIG _.
supplied to In this case, the original signal G is located at a time period (1H + τ) earlier than the original time point, so the signal _G7 is located at the original time point, and this signal _G7 is the resistor. This serves as a standard for ratio adjustment.

Furthermore, if the registration of the image pickup tubes 1G and 1R is correct, a signal R having the same phase as the signal _G7 is taken out from the image pickup tube 1R, but the image pickup tube 1R is When the scanning area Ar of the electron beam is shifted downward as shown by the broken line in FIG. 1A when viewed from the subject image (inverted image) of the image pickup tube 1R, the scanning area Ar of the electron beam advances as shown by the broken line in FIG. 3I. A signal R with a phase of
When there is a downward shift as shown by the chain line in FIG. 3I, a signal R with a delayed phase is obtained as shown by the chain line in FIG. 3I. Then, the phase amount θ of this signal R
corresponds to the magnitude of the vertical deviation of the scanning area Ar in the image pickup tube 1R.

This signal R is then supplied to the subtraction circuit 22 through the switch circuit 21 which has been switched to the state shown in the figure, and subtraction between the signal _G7 and R is performed.
The difference signal _G7 -R is taken out as shown in Figure E,
This signal _G7 -R is the sampling hold circuit 2
3,24. In this case, the signal
The polarity of G ₇ -R indicates the direction of shift in the vertical direction of the scanning area Ar of the electron beam in the red image pickup tube 1R, and the width θ indicates the magnitude of the shift.

Further, _the signal G ₁ is supplied to the delay circuit 12 to become the signal G ₂ which is further delayed by one horizontal period as shown in FIG. As shown in Figure 3E, the difference signal G
_-G2 is taken out, and this signal G- _G2 is supplied to the delay circuit 14 to produce a signal _S4 delayed by 1/2 pixel period as shown in FIG. A signal _S4 indicating the vertical edge of is taken. This signal _S4 is then supplied to the level discrimination circuit 16 through the switch circuit 15 which has been switched to the state shown in the figure, and the level is discriminated between levels _E3 and _E4 . An edge pulse P ₃ is formed as shown in FIG. 3H, and an edge pulse P ₄ is formed as shown in FIG. 3H.

In this case, as shown in FIG.
When the center area is divided into areas, and the center area is the upper center area, and the area to the right of the center is the area, when adjusting the image shown in FIG. In the controller 30, an enable signal _S16 that becomes "1" is generated during the area scanning period, and this signal _S16 is supplied to the discrimination circuit 16, so that the level discrimination in the discrimination circuit 16 is performed only during the area scanning period. It will be done.

Therefore, the discrimination circuit 16 obtains pulses P ₃ and P ₄ that indicate the vertical edges of the portion of the subject image located in the region. i.e. pulse
P ₃ and P ₄ indicate vertical edges within the region.

These pulses P ₃ and P ₄ are supplied as control signals to sampling and holding circuits 23 and 24, and the signal G ₇ -R is sampled and held. In this case, since the sampling and hold circuits 23 and 24 have capacitors for holding, the capacitors allow the pulses P ₃ ,
The signal G ₇ -R is integrated during the period when P ₄ is "1", and this integrated value is held during the period when P 4 is "0". Therefore, from the sampling hold circuit 23, a broken line (in the case of the broken line in FIG. 1A) or a chain line (in the case of the broken line in FIG. 1A) is shown in FIG. A DC voltage V ₃ whose polarity is reversed as shown by the dashed line A) is extracted. In addition, as shown in FIG. 3L, the sampling and holding circuit 24 outputs a DC voltage whose polarity changes in the same way and whose polarity is opposite to that of the voltage _V3 .
V ₄ is taken out.

Then, these voltages V ₃ and V ₄ are applied to the voltage comparator circuit 25.
When V ₃ < V ₄ (dotted line), “0”
Then, when V ₃ > V ₄ (dotted line), a comparison output S ₅ that becomes “1” is taken out, and this signal S ₅ is supplied to the up-down counter 26 as a control signal for the count mode, and the counter 26 A vertical synchronization pulse Pv is supplied from the controller 30 as a count input. Then, the count value of the counter 16 is passed through the multiplexer 27 to D-A.
The DC voltage V ₈ is supplied to the converter 28 and set to a level corresponding to the count value, and during the adjustment shown in _FIG . It is also supplied to the vertical deflection plate 2R through the amplifier 43A and the adder circuit 51 as a correction voltage.

That is, the level of the output signal _S5 of the voltage comparison circuit 25 indicates the direction of vertical deviation of the scanning area Ar with respect to the scanning area Ag. Then, the counter 26 counts up the pulse Pv (when _{S 5 =} “0”) or counts down (when S ₅ =“1”) according to this signal S5. In addition, the converter 28 converts the count value into an analog voltage
_V7 to control the vertical scanning range of the image pickup tube 1R.

Note that the gate circuits 41A to 41F, the capacitors 42A to 42F, and the amplifiers 43A to 43F correspond to the adjustment items in FIGS. 1A to 1F. In addition, capacitors 42A to 42F are used to hold the correction voltage (adjusted voltage) obtained by the adjustment when the corresponding adjustment among the adjustment items shown in FIG. 1 A to F is completed. It is.

Therefore, if the scanning area Ar is shifted upwards when viewed from the subject image of the image pickup tube 1R, as shown by the broken line in FIG. Since the phase advances, S ₅ = “0” and the counter 26 counts up the pulse Pv. Therefore, the voltage V ₈ increases, so the image pickup tube 1
The R scanning area Ar changes downward when viewed from the subject image.

On the other hand, as shown by the chain line in FIG. 1A, the image pickup tube 1
When the scanning area Ar is shifted downward when viewed from the subject image in R, the phase of the signal R is delayed as shown by the chain _line in FIG. counts down the pulse Pv, and therefore the voltage _V8 decreases, so the scanning area Ar of the image pickup tube 1R changes upward as viewed from the subject image.

Therefore, the scanning area of the electron beam of the image pickup tube 1R
Even if Ar is shifted vertically as shown in Figure 1A, this vertical shift is equal to 1 of the pulse Pv.
Each time it is corrected to 0 and converged.

Then, after a predetermined period of time, this deviation becomes smaller and falls within the permissible range (at this time, the signal S ₅
repeats "0" and "1" for each pulse Pv), the enable signal from the controller 30 becomes "0", which causes the counter 26 to stop counting and the gate circuit 41A to turn off. be done. However, at this time, the voltage V ₈ is stored in the capacitor 42A, so from now on, the voltage V ₈ stored in the capacitor 42A is supplied to the deflection plate 2R as a correction voltage for the adjustment item in FIG. 1A. It becomes like this.

Also, at this time, the count value of the counter 26 is supplied to the memory 29 and written to a predetermined address Aa.

Therefore, the positional relationship between the subject image in the image pickup tube 1R and the scanning area Ar of the electron beam coincides in the vertical direction with respect to the positional relationship of the reference image pickup tube 1G. It is maintained by the voltage of . In other words, the adjustment shown in FIG. 1A has been completed. Also, the correction voltage data at this time is the capacitor 42A.
is stored as an analog value, and stored as a digital value at address Aa of the memory 29.

When the adjustment shown in FIG _. 1A is completed, the adjustment shown in FIG. The signal G ₈ is delayed by a prime period, and the signal G ₈ and the signal G ₁ are subtracted to produce a difference signal G ₁ − G ₈
That is, signals G ₁ -G ₈ indicating the horizontal edges of the reference green object image are extracted. These signals G ₁ -G ₈ are supplied to the level discrimination circuit 16 through the switch circuit 15, and are also applied to the scanning area Ar during the adjustment shown in FIG.
The horizontal shift is detected in the area, and an enable signal _S16 that becomes "1" is supplied to the discrimination circuit 16 during the area scanning period.

Therefore, in the region of the image pickup tube 1R, if the electron beam is shifted to the right when viewed from the subject image, as shown by the broken line in FIG. 1D, then V ₃ <0, V ₄ >0, and S ₅ = If it becomes "0" and is shifted to the left as shown by the chain line in FIG. 1D, V ₃ >0, V ₄ <0, and S ₅ = "1".

Then, a voltage _V8 is generated by this signal _S5 in the same manner as in the case of FIG. 1A, and during the adjustment in _FIG . It is supplied to a memory capacitor 42D and stored therein, and is further supplied to an adder circuit 5 through an amplifier 43D.
2 to the horizontal deflection plate 3R as a correction voltage.

Therefore, the scanning area is determined in the same way as in the case of FIG.
The horizontal position of Ar is controlled, and the positional relationship between the subject image in the image pickup tube 1R and the scanning area Ar of the electron beam horizontally matches the positional relationship of the reference image pickup tube 1G. The state is maintained by the voltage on capacitor 42D. In other words, the adjustment shown in FIG. 1D has been completed. In addition, at this time, the correction voltage of the capacitor 42D is
As in the case of FIG. 1A, it is stored at address Ad in the memory 29.

If the green subject image and red subject image before adjustment in Figure 1 A and D are shown as images Ig and Ir in Figure 5 A, then Figure 1 A and D
After the adjustment, the centering is achieved as shown in FIG. 5B.

After the adjustment shown in FIG. 1D is completed, the adjustment shown in FIG. 1B is then performed. That is, in this case, the vertical size deviation of the scanning area Ar is
The signal S ₄ is supplied to the level discrimination circuit 16 through the switch circuit 5, and the enable signal S ₁₆ is set to "1" during the region scanning period.

When the voltage _V8 is adjusted as shown in Figure 1B,
The signal is supplied to a capacitor 42B through a gate circuit 41B, and is also supplied as a gain control signal to a variable gain amplifier 53B through an amplifier 43B. Further, the vertical deflection voltage from the deflection circuit 4 is supplied to the vertical deflection plate 2R through the amplifier 53B and further through the adder circuit 51.

In this case, the amplifier 53B is, for example, the sixth
As shown in the figure, a constant gain inverting amplifier 531
, a non-inverting variable gain amplifier 532 controlled by the voltage _V8 , and an adder circuit 533, and the level and phase of the output of the amplifier 53B with respect to changes in the voltage _V8 are shown in FIGS. 7A to E. (Other amplifiers 53C to 5
The same applies to 3F).

Therefore, the scanning area is as shown by the dashed line in FIG.
When the vertical size of Ar is large, the phase of the signal R advances as shown by the broken line in FIG. 3I when scanning the area, so that S ₅ =“0” and the voltage V ₈ increases. Therefore, the vertical deflection voltage supplied to the deflection plate 2R through this amplifier 53B is applied to the deflection circuit 4.
Since the phase is opposite to the main vertical deflection voltage supplied through the line → adder circuit 51 → deflection plate 2R, the vertical size of the scanning area Ar becomes small.

On the other hand, as shown by the chain line in Figure 1B, the scanning area
When the vertical size of Ar is small, the phase of the signal R is delayed as shown by the chain line in FIG. 3I when scanning the area, so S ₅ becomes "1" and the voltage V ₈ decreases. Therefore, the vertical deflection voltage supplied to the deflection plate 2R through this amplifier 53B is in phase with the main vertical deflection voltage, so that the scanning area
The vertical size of Ar increases.

Therefore, after a predetermined period of time, the vertical size of the scanning area Ar converges to the vertical size of the reference scanning area Ag, and in this state, the signal _S5 repeats "1" and "0".

Therefore, an enable signal from the controller 30 causes the counter 26 to stop counting and the gate circuit 41B to be turned off. and,
After that, the scanning area is determined by the voltage of the capacitor 42B.
The vertical size of Ar is held. That is,
This completes the adjustment shown in FIG. 1B.

Next, regarding the adjustment shown in FIG. ₁ −G ₈ is supplied.

Further, the voltage _V8 is supplied to the capacitor 42F through the gate circuit 41F, and is also supplied to the amplifier 4
It is supplied as a control signal to variable gain amplifier 53F through 3F. Then, the vertical deflection voltage (vertical sawtooth voltage) from the deflection circuit 4 passes through the amplifier 53G and further passes through the addition circuit 52 to the horizontal deflection plate 3R.
supplied to

Therefore, after a predetermined period of time, the horizontal distortion of the scanning area Ar is corrected, and the adjustment shown in FIG. 1F is completed.

Therefore, the subject images Ir and Ig in Figure 5B are as shown in Figure 5C.
As shown in , the registration is further removed.

Then, the adjustment shown in FIG. 1C is performed. In this case, the magnitude of distortion in the vertical direction of the scanning area Ar is detected in the area, the switch circuit 15 is in the state shown, and the circuits 41C, 42
C, 43C are used, and a horizontal deflection voltage (horizontal sawtooth voltage) for correction is supplied to the vertical deflection plate 2R through an amplifier 53G.

Furthermore, the adjustment shown in Figure 1E is then performed,
In this case, the horizontal size of the scanning area Ar is detected in the area and the switch circuit 15
is the opposite state to that shown in the figure, and the circuits 41E, 42E,
43E is used. Then, a horizontal deflection voltage for correction is supplied to the horizontal deflection plate 3R through the amplifier 53E.

Therefore, the subject images Ir and Ig in Figure 5C are as shown in Figure 5D.
The registration will be established as shown in the figure.

When the adjustment shown in FIG. 1E is completed, the adjustment from FIG. 1A to FIG. 1E is repeated again. This is to improve registration accuracy.

When all the above adjustments are completed, the switch circuit 21 is switched to the opposite state as shown in the figure.
Similar adjustments are made to the image pickup tube 1B.

After these adjustments are completed, memory 2
The data of the voltage V ₈ at the time of each adjustment stored in the controller 9 is sequentially and repeatedly read out, and this read data is supplied to the D-A converter 28 through the multiplexer 27, and from the converter 28 the voltage V 8 at the time of each adjustment is read out. ₈ are taken out repeatedly in sequence.

Then, this voltage _V8 is applied to the gate circuit 41A~
41F and the similar gate circuit of the blue channel, the voltage V ₈ of the capacitor is supplied through the gate circuit corresponding to the voltage V 8 to the capacitors 42A to 42F and the corresponding capacitor of the similar capacitor of the blue channel, so that the voltage V ₈ of the capacitor is Refreshed.

In this way, the registration of the image pickup tubes 1R and 1B is adjusted. During this adjustment, the pulses P ₃ and P ₄ are supplied to the controller 30, and the count value of the counter 26 reaches the maximum value or the minimum value. When the adjustment is not completed even if the signal S ₄ or G ₁ - G ₈ has a small number of pulses, i.e.
When the number of edges in the subject image is small, and when the count value does not converge even after up-counting and down-counting is performed several times in the counter 26, these are determined by the controller 30, and the adjustment is aborted as an abnormal state. An error message is displayed.

As described above, according to the present invention, the registration adjustment of a multi-tube color camera can be performed, and since the adjustment can be performed automatically, the image pickup tubes 1G, 1R, and 1B can be replaced. At the same time, the exchange can be performed quickly and accurately without causing individual differences due to differences in the skill level of the person performing the exchange. Furthermore, no special pattern such as a V-shaped pattern is required during adjustment. Furthermore, it is easy to configure and does not require a high-speed clock.
It can be built into a portable color camera.

As mentioned above, with an electrostatic deflection type image pickup tube,
Generally, the adjustments shown in Figure 1 A to F are sufficient, but if you wish to make more precise registration adjustments, adjust the vertical and horizontal nonlinear distortions as shown in Figure 1 G and H. All you have to do is In this case, the magnitude of the distortion is detected in the area, and in the case of G in Figure 1, a parabolic voltage with a horizontal period is supplied to the vertical deflection plate, and in the case of H in Figure 1, the parabolic voltage with a vertical period is supplied to the vertical deflection plate. It is sufficient to supply it to the deflection plate.

Moreover, the order of each adjustment can also be changed.
Furthermore, a luminance signal is extracted from the first image pickup tube,
The present invention can also be applied to other types of color cameras that take out carrier color signals from image pickup tubes.

[Brief explanation of drawings]

1 and 3 to 7 are diagrams for explaining this invention, and FIG. 2 is a system diagram of an example of this invention. 4 and 5 are deflection circuits, 11, 12, 14, 17,
18 is a delay circuit, 16 is a level discrimination circuit, 23,
24 is a sampling hold circuit, 26 is a counter, 28 is a DA converter, and 29 is a memory.

Claims (1)

[Claims] 1 Divide the screen into a plurality of scanning areas, extract a signal indicating an edge in a predetermined divided area of the first subject image supplied to the first image pickup tube from the output signal of the first image pickup tube, and A difference signal between the output signal of the first image pickup tube and the output signal of the second image pickup tube is sampled using the edge signal, and a second signal corresponding to the predetermined divided scanning area is supplied to the second image pickup tube. A deviation between the scanning area of the electron beam for the subject image and a predetermined scanning area of the electron beam for the first subject image is detected, and this detection output is supplied to the deflection means of the second image pickup tube to A registration adjustment method for a multi-tube color television camera, which adjusts the registration of the second subject image with respect to the first subject image.