JP3183006B2 - TV camera - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a television camera for picking up images in a non-interlace system.

[0002]

2. Description of the Related Art The terrestrial broadcasting system currently used in Japan is an interlace (interlaced scanning) system having an aspect ratio of 4: 3. In recent years, there has been a demand for a wider screen and higher image quality of the terrestrial broadcasting, and the Broadcasting Technology Development Association (BTA) has made the screen wider (while maintaining compatibility with the current terrestrial broadcasting system). Aspect ratio 1
6: 9) and the second generation E which is a new broadcasting system aiming at high picture quality
DTV is being studied.

In the case of the interlace method, the field is switched every 1/60 second, so that even when a still object is imaged, a line flicker occurs at the outline of the object and the image flickers. Also, when capturing a moving object, two adjacent
Since there is an interval of 1/60 second between scanning of the scanning lines, the outline of the object is displayed shifted for each line and the resolution is reduced.

Therefore, as one method for realizing a high image quality of a screen, non-interlace (progressive) in which 525 horizontal scans are performed in one field (1/60 second).
Development of a television camera of the system is in progress. In the case of the non-interlace method, 525 lines are completely scanned in 1/60 second, so that line flicker does not occur.
Since the difference in scanning time between two adjacent scanning lines is much smaller than in the case of the interlaced system, the displacement of the outline when capturing a moving object is reduced, and a higher quality image is obtained.

FIG. 3 is a block diagram showing a conventional non-interlaced television camera.

In FIG. 3, reference numeral 1 denotes an image pickup device for picking up an image in a non-interlaced manner; 7, an image display device for displaying a video signal obtained by the image pickup device 1 as a non-interlaced image; The system 5 is a focus adjusting means for adjusting the focus of the optical system 4.

A conventional non-interlaced television camera will be described below with reference to FIG.

[0008] The non-interlaced video signal output from the imaging device 1 is output to the image display device 7. The cameraman who operates this television camera sees the image being shot by the image display device 7 in real time, and refers to the contour portion of the object reflected by the optical system of the imaging device 1 by referring to the contour portion of the object being reflected. 4 Adjust the focus.

[0009]

However, if a non-interlaced image display device is used as this image display device, since the image quality is high, it is necessary to detect a slight shift in focus by human vision and correct it. Becomes difficult.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a non-interlaced television camera capable of solving the above-mentioned problems and easily detecting a focus shift of an optical system of the television camera by human vision. I do.

[0011]

In order to achieve the above object, a television camera according to the present invention comprises an image pickup device for picking up images in a non-interlaced system, and a non-interlaced video signal obtained by the image pickup device. A non-interlace / interlace conversion circuit for converting a scanning line into a video signal of an interlace system by thinning the scanning lines in a vertical direction, and an image display device for displaying a video signal obtained by the non-interlace / interlace conversion circuit as an image of an interlace system Focus adjustment means for adjusting the focus of the optical system of the imaging device, wherein the focus adjustment means while a human looks at the image display device
The focus can be adjusted by operating
Sign .

A television camera according to the present invention includes an image pickup apparatus that picks up an image in a non-interlaced manner and outputs two interlaced video signals consisting of main scanning and sub-scanning . An image display device that displays one interlaced video signal as an image among the video signal outputs as an image, and a focus adjustment unit that adjusts a focus of an optical system of the imaging device, so that a human can display an image.
Operate the focus adjustment means while looking at the device to focus.
It is characterized in that it is possible to perform

[0013]

With this configuration, in the television camera of the present invention, a high-quality video signal picked up by a non-interlaced image pickup device is thinned by a non-interlaced / interlaced conversion circuit in a scanning line direction in the vertical direction of the image. Convert to interlaced video signal,
It can be displayed. In this non-interlaced / interlaced conversion, since a low-pass filter is not applied simply by thinning out the vertical scanning lines, aliasing occurs in the vertical frequency components, and the largest frequency component is obtained when the focus is best. The image flickers. When the image is out of focus, only a low-frequency component exists in the vertical direction of the image, and no aliasing occurs because no high-frequency component exists. The cameraman who operates the television camera having this configuration can adjust the focus by the focus adjustment unit while watching such an image, so that the adjustment can be easily performed by adjusting the focus to a place where the image flickers most.

Further, as the interlaced image display device, a device conventionally used in an interlaced camera can be used as it is. Therefore, a non-interlaced image display device was newly developed and used. A non-interlaced television camera can be realized at a lower cost than in the case.

That is, the present invention makes it possible to easily detect the focus shift of the optical system of a television camera by human vision by positively utilizing the decrease in the vertical resolution of an image, which is a drawback of the interlace system. Therefore, a non-interlaced television camera with easy focus adjustment can be realized at low cost.

[0016]

FIG. 1 is a block diagram showing a configuration of a television camera according to a first embodiment of the present invention.

In FIG. 1, reference numeral 1 denotes an image pickup apparatus for picking up an image in a non-interlaced manner, and 2 denotes an interlaced image signal obtained by the image pickup apparatus 1 by thinning out scanning lines in the vertical direction of the image. A non-interlace / interlace conversion circuit for converting the video signal into an image signal, an image display device for displaying a video signal obtained by the non-interlace / interlace conversion circuit 2 as an image of an interlace system, 4 an optical system of the imaging device 1, and 5 It is a focus adjustment unit that adjusts the focus of the optical system 4.

The operation of the television camera according to the first embodiment of the present invention will be described below with reference to FIG. Since the television camera according to the present embodiment is configured as described above, an image captured by the imaging device 1 is output as a non-interlaced video signal. This video signal is input to the non-interlace / interlace conversion circuit 2, and is converted into an interlace video signal by thinning out scanning lines in the vertical direction of the image, and is output. The video signal converted to the interlace format is input to the image display device 3,
The image is displayed as an interlaced image. Since the image displayed on the image display device 3 simply performs thinning-out of the vertical scanning lines from the non-interlaced image and does not apply a low-pass filter, aliasing occurs in the frequency component in the vertical direction. When the optical system 4 is most focused, the largest image flicker is observed. The cameraman can easily adjust the focus by the focus adjusting means 5 while watching the flickering of the image.

FIG. 2 is a block diagram showing a configuration of a television camera according to a second embodiment of the present invention.

[0020] In FIG. 2, 6 imaging device for outputting a video signal of two lines interlaced consisting main scanning and sub-scanning by capturing an image noninterlaced, 3 video signals of two systems of the imaging apparatus 6 This is an image display device that displays one interlaced video signal as an image among the outputs, and is the same as the image display device 3 of the television camera of the first embodiment shown in FIG. The optical system 4 and the focus adjusting means 5 are the same as the optical system 4 and the focus adjusting means 5 of the television camera of the first embodiment shown in FIG.

The operation of the television camera according to the second embodiment of the present invention will be described below with reference to FIG. Since the television camera according to the present embodiment is configured as described above, the image captured by the imaging device 6 is output as a two-system interlaced video signal composed of main scanning. 2 of this imaging device 6
One of the video signal outputs of the system , for example, a main scanning interlaced video signal is input to the image display device 3,
The image is displayed as an interlaced image. Since only one of the two interlaced video signals obtained by the imaging device 6 is displayed by the image display device 3, it is folded back into a vertical frequency component similarly to the television camera of the first embodiment of the present invention. When the optical system 4 is most focused, the largest image flicker is seen. The cameraman can easily adjust the focus by the focus adjusting means 5 while watching the flickering of the image.

Further, as the interlaced image display device used in the television cameras of the first and second embodiments of the present invention, the one conventionally used in interlaced cameras can be used as it is. A non-interlaced television camera can be realized at lower cost than when a non-interlaced image display device is newly developed and used.

That is, the television camera of the present invention has a configuration as described above, and actively utilizes the reduction in the vertical resolution of an image, which is a drawback of the interlaced system.
The present invention makes it possible to easily detect a focus shift of the optical system of a television camera by human vision, and to realize a non-interlaced television camera with easy focus adjustment at low cost.

[0024]

As described above, the television camera of the present invention has the following features.
Since it is possible to easily detect a focus shift of an optical system of a television camera by human vision, it is possible to realize a non-interlaced television camera with easy focus adjustment at low cost.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a television camera according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a television camera according to a second embodiment of the present invention.

FIG. 3 is a block diagram showing a configuration of a conventional non-interlaced television camera.

[Explanation of symbols]

 1, 6 Non-interlace type imaging device 2 Non-interlace / interlace conversion circuit 3 Interlace type image display device 4 Optical system of imaging device 5 Focus adjustment means

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-4-306081 (JP, A) JP-A-1-137895 (JP, A) JP-A-62-64188 (JP, A) JP-A-4-64 306081 (JP, A) JP-A-5-260360 (JP, A) JP-A-63-73213 (JP, A) JP-A-1-137895 (JP, A) JP-A-4-354273 (JP, A) JP-A-4-354274 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H04N 5/222-5/257

Claims (2)

(57) [Claims] 1. An image pickup apparatus for picking up an image in a non-interlace system, and a non-interlace video signal obtained by the image pickup device is converted into an interlace video signal by thinning out scanning lines in the vertical direction of the image. A non-interlace / interlace conversion circuit, an image display device for displaying a video signal obtained by the non-interlace / interlace conversion circuit as an interlaced image, and a focus adjustment unit for adjusting a focus of an optical system of the imaging device. Provided that human beings consider the image display device
The focus adjustment by operating the focus adjustment means.
A television camera, which can be performed . Wherein an imaging device for outputting an image signal of the two systems of interlaced by capturing an image noninterlaced made from the main scanning and sub scanning, one of the video signal output of the two systems of the imaging apparatus an image display device for displaying a video signal of an interlace method as an image, and a focus adjustment means for adjusting the focus of the optical system of the imaging device, but humans considered the image display device
The focus adjustment by operating the focus adjustment means.
A television camera, which can be performed .