JPS637094A - Lens convergence control system for television camera - Google Patents

Abstract

PURPOSE:To make the contrast of right and left pictures projected on monitor screens always in the same level by mixing video signals obtained from two television cameras of a stereoscopic television system and stopping the lenses of two television cameras at the same time and in the same level based on the average luminance level of the mixed signal. CONSTITUTION:Television cameras 1 and 2 outputs the video signals 100 and 200 of the same object to be taken to a mixing circuit 12. The mixing circuit 12 consists of a switching switch which selects either video signal 100 or 200 alternately to output every field and outputs a mixing signal 300. The mixing signal 300 has a signal form where the video signal 100 and 200 are alternately replaced every field. A luminance level detection circuit 13 detects the average luminance level F of the mixing signal 300, and outputs it to a stop drive circuit 14. The stop drive circuit 14 controls the stops of the respective lens parts 4 and 5 at the same time and in the same level so as to make the contrast of the video signals picked up by the television cameras 1 and 2 based on the average luminance level F proper.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a lens aperture control method for a television camera constituting a stereoscopic television system.

(Prior Art) Conventionally, a three-dimensional television system is configured as shown in FIG. That is, two television cameras 1 and 2 are arranged at an appropriate interval so that their optical axes are parallel to each other. Each television camera 1.2 outputs a video signal obtained by imaging the same subject 3 with lenses 4, 5 to the stereoscopic camera controller 8 via a cable 6.7. A stereoscopic camera controller 8 alternately switches the video signals inputted from the television cameras 1 and 2 for each field and displays them on a monitor 9.
Output to. Therefore, the monitor 9 displays an image 10A captured by the television camera 1 and an image 10A captured by the television camera 2.
B and B are projected alternately for each field.

On the other hand, the three-dimensional camera controller 8 opens and closes the shutters of the parts of the stereoscopic glasses 11 that correspond to the left and right eyes of the viewer for each field, and the viewer wearing the three-dimensional glasses 11 uses the right TV camera 1 on the monitor 9 to capture images. When the image taken by the TV camera 2 on the left side is captured, the user sees it with the right eye, and when the image captured by the left TV camera 2 is captured, the user sees it with the left eye. Therefore, the viewer can view the image displayed on the monitor 9 in three dimensions.

By the way, the apertures of the lenses 4 and 5 of the television cameras 1 and 2 separately detect the brightness levels of the video signals sent from the television cameras 1 and 2 separately, and use these detected values to obtain appropriate exposure. are adjusted separately. Therefore,
When a spot of strong light enters the lens of either the TV camera 1 or 2, the aperture of the lens of only one TV camera is narrowed down, and the contrast between the right image and the left image displayed on the monitor screen 9 increases. This difference caused the screen to flicker to the viewer, making it extremely unsightly.

(Problems to be Solved by the Invention) In the conventional television camera lens aperture control method, the lens apertures of two television cameras are controlled separately based on the brightness level of the video signal obtained from each television camera. ing. Therefore, if a spot of strong light falls on one of the TV cameras, the image displayed on the monitor will flicker, resulting in an extremely unsightly screen.

SUMMARY OF THE INVENTION The present invention aims to eliminate the above-mentioned drawbacks and provides a lens aperture control method for a television camera that does not cause a difference in contrast between left and right images displayed on a monitor screen.

[Configuration of the Invention (Means for Solving the Problems) The aperture control method for the lens of a television camera according to the present invention includes a mixing means for mixing video signals from two television cameras;
a brightness level detection means for detecting the brightness level of the mixed video signal;
The system consists of an aperture driving means that simultaneously narrows down the lenses of the two television cameras to the same level.

(Function) In the television camera lens aperture control method 1 of the present invention, the aperture driving means simultaneously controls the apertures of the lenses of two television cameras based on the luminance level of the video signal mixed by the mixing means. In addition, because the focus is focused to the same level, even if strong light such as a spot is incident on one TV camera, the lenses of both TV cameras are focused at the same time and to the same level, so the left and right images displayed on the monitor screen will be different. There is no difference in contrast.

(Embodiment) An embodiment of the present invention will be described below with reference to the drawings, in which the same parts as in the conventional example are denoted by the same reference numerals. FIG. 1 is a block diagram showing a lens aperture control device for a television camera, which is an embodiment of the present invention. 1°2 is an appropriate distance so that the optical axes are parallel to each other.
4 is a lens section of the television camera 1, 5 is a lens section of the television camera 2, and 12 is a video signal 100 output from the television camera 1 and a video signal 2 output from the television camera 2.
00 into one video signal; 13 is a brightness level detection circuit that detects the average brightness level of the video signal output from the mixing circuit; 14 is a brightness level detection circuit that responds to the brightness level given from the brightness level detection circuit 13; lens parts 4, 5
This is an aperture drive circuit that simultaneously narrows down the apertures of the two to the same level.

Next, the operation of this embodiment will be explained. TV camera 1
, 2 output video signals 100.200 of the same subject as shown in FIGS. 2(A) and 2(B) to the mixing circuit 12. The mixing circuit 12 consists of a changeover switch 121 (usually composed of a switching transistor or the like) that alternately selects and outputs either the video signal 100 or 200 for each field, as shown in FIG. 3, for example. ing. This changeover switch 121 is alternately switched by a field switching signal 400 sent from a control section (not shown), and this mixed signal 300 outputs a video signal for each field as shown in FIG. 2(C). @100
The signal has a signal form in which .degree. 200 is alternately switched. The brightness level detection circuit 13 detects the average brightness level of the input mixed signal 300 as shown in FIG. 2(C), and outputs it to the aperture drive circuit 14.

The diaphragm drive circuit 14 converts the video signals captured by the television cameras 1 and 2 based on this average brightness level F.
Control is performed so that the apertures of the respective lens sections 4 and 5 are simultaneously stopped down to the same level so that the apertures become appropriate.

According to this embodiment, a spot-like high brightness level as shown in FIG. 2(B) occurs in the video signal of the television camera 2, and the average brightness level F of this video signal is as shown in FIG. 2(A).
Even if the average brightness level D of the video signal 100 from the television camera 1 shown in
The two lens sections 4.degree.5 are simultaneously stopped by a common average brightness level F. Therefore, there is no difference in contrast between the video signals 100 and 200 output from the television cameras 1 and 2, and no flickering occurs in the image of the subject displayed on the monitor screen.
The screen can be easily viewed.

FIG. 4 is a diagram showing another example of the configuration of the mixing circuit 12 shown in FIG. A video signal of 100.200 is input. In this case, the mixed signal 300 obtained by simply adding the video signals 100 and 200 will be sent to the brightness level detection circuit 13, but in this case as well, the brightness level at which the lens sections 4 and 5 of each television camera are focused is Since they are common, the same effects as in the above embodiment can be obtained.

[Effects of the Invention] As described above, according to the television camera lens aperture control method of the present invention, video signals obtained from two television cameras are mixed, and the two video signals are adjusted based on the average brightness level of this mixed signal. By controlling the apertures of the lenses of the two TV cameras simultaneously and to the same level, the contrast of the images from the two TV cameras that are alternately projected on the monitor screen is always at the same level, and a good screen can always be maintained. effective.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing a lens aperture control device for a television camera which is an embodiment of the present invention, FIG. 2 is a diagram showing an example of a signal waveform used in the device shown in FIG. 1, and FIG. A diagram showing an example of the mixing circuit 12, FIG. 4 is a diagram showing an example of the mixing circuit 12.
FIG. 5 is a diagram showing an example of a stereoscopic television system. 1.2...TV camera 4.5...Lens unit 12...Mixing circuit 13...Brightness level detection circuit 14...Aperture drive circuit Agent Patent attorney Nori Chika Ken Shu Kanshu Sanno - 2nd Figure 3 Figure 4 Figure 5

Claims (2)

[Claims] (1) In a lens aperture control method for a television camera in a 3D television system that alternately displays video signals from two television cameras on a monitor field by field, the video signals from the two television cameras are mixed. a mixing means for outputting, a brightness level detecting means for detecting the brightness level of the video signal output from the mixing means, and a lens of the two television cameras according to the brightness level detected by the brightness level detecting means. 1. A lens aperture control system for a television camera, comprising: an aperture driving means for simultaneously and to the same level. (2) Claim (1) characterized in that the mixing means is a changeover switch that alternately switches the output of the video signal input from each television camera for each field.
Lens aperture control method for television cameras as described in Section 2.