JPH03131191A - Image pickup device - Google Patents

Abstract

PURPOSE:To attain tracking adjustment easily and quickly by providing a 1st drive means moving at least one image pickup element P among plural image pickup elements on an optical axis manually and a 2nd drive means moving the element on the optical axis by a motor drive. CONSTITUTION:When a micrometer 10 is turned manually, its tip is moved on the optical axis straightforward. A moving base 12 is moved by a frame 11 in contact via a piezo element 14 by the movement of the tip of the micrometer 10 to apply coarse adjustment of the image pickup element 16 in the direction of optical axis. On the other hand, a video signal obtained from the image pickup element 16 via a connector cable 18 is evaluated by a video evaluation circuit 101. The position and the direction or the like of the image pickup element 16 are evaluated and an evaluation signal obtained in this case is sent to a drive control circuit 19. Then the drive control circuit 19 expands or contract the piezo element 14 by a prescribed quantity to apply fine adjustment to the image pickup element 16 in the direction of the optical axis with respect to the moving base 12.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to an imaging device used in a color television camera, etc., and particularly to a method for improving tracking adjustment of the color television camera when a solid-state image sensor is used as an imaging means. The present invention relates to an imaging device configured to perform the following operations.

(Prior art) Conventionally, in color television cameras, the light flux from the photographing lens is separated into multiple colors of light, such as red, green, etc., using a color separation prism.
The light is separated into three blue colors, and an object image based on each color light is formed on the image sensor surface. Color reproduction is then performed by obtaining color video signals from each image sensor. Since the center (fundamental) wavelength of each of these three color lights differs by a predetermined amount, due to the influence of the axial chromatic aberration of the photographing lens, the imaging positions of the object images based on each color light in the optical axis direction may shift from each other, resulting in tracking errors. It's coming.

In addition, in color television cameras, a zoom lens is generally used as the darkest lens. With zoom lenses, axial chromatic aberration changes depending on the zoom position due to magnification change, so 3.
The imaging plane of the object image of colored light also varies with each zoom position, which appears as a tracking error.

In conventional imaging devices, a holding member that holds the color separation prism and a holding member that holds the image pickup tube exist separately. One holding member is fixed to the other holding member with screws, etc., and one optical system unit is assembled into one optical system unit. It was composed.

For this reason, a moving mechanism is provided on the object side of a holding member that holds the image pickup tube, and the moving mechanism moves the image pickup tube to perform tracking adjustment.

(Problem to be solved by the invention) However, when using a solid-state image sensor, which has been rapidly put into practical use in recent years, it becomes mechanically complicated if the solid-state image sensor is configured away from the exit surface of the color separation prism. In many cases, a shooting lens (master lens) is used as a standard.
is determined, and a solid-state image sensor is fixed to the exit surface of the color separation prism by adhesive or the like in accordance with the master lens.

In such a configuration, there is a problem in that tracking cannot be adjusted by moving the solid-state image sensor. Therefore, when you change the shooting lens or change the magnification using a zoom lens, etc., the effect of the axial chromatic aberration of the shooting lens or zoom lens appears on the screen, resulting in an out-of-focus image. There was a point.

For this reason, in conventional imaging devices that target solid-state image sensors, it is necessary to better correct the axial chromatic aberration of the imaging system. There was a problem in that the number of sheets had to be increased.

When the present invention configures an imaging device using a solid-state imaging device, the solid-state imaging device is not fixed to the exit surface of the color separation prism but is separated from the exit surface, and a predetermined imaging device is driven by an appropriately configured driving means. An object of the present invention is to provide an imaging device in which tracking can be easily and quickly adjusted by moving it in the optical axis direction.

(Means for Solving the Problems) The imaging device of the present invention is an imaging device that separates a luminous flux from a photographing lens into a plurality of colored luminous fluxes through a color separation optical system, and then guides the light to each imaging element. a first drive means for manually moving at least one image sensor P among the plurality of image sensors on the optical axis; a video signal from the image sensor P is evaluated by a video evaluation circuit; The second driving means is provided for electrically moving the image sensor P along the optical axis based on the output signal of the image sensor P.

(Embodiment) Fig. 1 is a schematic diagram of the main parts of an embodiment in which the present invention is applied to a color television camera, Fig. 2 is a detailed view of a portion of Fig. 1 viewed from B, and Fig. 3 is Fig. 2. FIG.

In the figure, 1 is an 11M2 lens, which is made up of, for example, a zoom lens. 2 is a filter member for near-infrared cut and color temperature conversion, and 3 is a color separation prism, which separates the light flux from the photographic lens 1 into three colored lights, for example, red, green, and blue. 4a.

4b and 4c are tracking adjustment mechanism sections provided independently, one of which is connected to the second tracking adjustment mechanism section.
As shown in the figure, it has a solid-state image sensor 16, and the image sensor 1
6 is moved in the optical axis direction by a predetermined drive of -1 step as will be described later, thereby performing tracking adjustment.

Reference numeral 5 denotes an optical base on which the color separation prism 3 and tracking adjustment mechanism sections 4a, 4b, and 4c are mounted. 6 is a camera base on which optical members such as a field lens, a relay lens, and a filter are fixed.

In this embodiment, an object image formed by a photographing lens 1 is separated into three colored object images by a color separation prism 3 via a filter member 2, and the images are formed on each image sensor surface. Then, convert the object image based on each color light into an electrical signal,
After signal processing, etc., a color image is obtained.

Next, FIG. 2 shows a case where tracking adjustment is performed by moving the image sensor 16 on the optical axis.

A pedestal 7 supports the prism unit 102. 8 is a fixed base of the tracking adjustment mechanism section 4a (4b, 4c). Reference numeral 10 denotes a micrometer, which corresponds to the first driving means and is manually rotated to move the movable base 1, which will be described later.
2 is moved in the optical axis direction. 9 is a micro support plate, which supports the micrometer 10. 11 is a top, which is fixed to the tip of the micrometer 10.

12 is a movable base to which the top 11 is attached, and 13 is a linear bearing, which is provided between the fixed base 8 and the movable base 12, and allows the movable base 12 to move smoothly.

14 is a piezo element, which is fixed to the frame 11.

Reference numeral 16 represents an image sensor (such as a CCD), and 15 represents an image sensor support plate, which holds the image sensor 16. 17 is a printed circuit board, which is connected to the image sensor 16. A connector cable 18 is connected to the printed circuit board 17. Reference numeral 19 denotes a drive control circuit, which corresponds to a second drive means, and expands and contracts the optical element 4 based on a signal from a video evaluation circuit 101, which will be described later, to move the movable base 12 along the optical axis.

Note that a spring (
(not shown) is provided, and the tip of the micrometer 10 is configured to always come into contact with the top 11 via the piezo element 14.

101 is a video evaluation circuit, and a connector cable 18
A video signal obtained from the image sensor 16 via the image sensor 16, for example, a video signal related to the focus state, is evaluated and the evaluation signal is transmitted to the drive control circuit 19.

In this embodiment, when the micrometer 10 is manually rotated, its tip moves linearly in the optical axis direction. The movable base 12 is moved by the top 11 that comes into contact with the micrometer 10 via the piezo element 14 as the tip of the micrometer 10 moves. This performs rough adjustment of the optical axis direction of the image sensor 16.

On the other hand, the video evaluation circuit 101 evaluates the video signal obtained from the image sensor 16 via the connector cable 18, evaluates the position and direction of the image sensor 1 and 6 that should be in focus, and performs the evaluation at this time. A signal is sent to the drive control circuit 19. The drive control circuit 19 expands and contracts the piezo element 14 by a predetermined amount to finely adjust the optical axis direction of the image pickup element 16 provided with respect to the movable base 12.

In this way, in this embodiment, the first. Imaging device 1 fixed relative to movable base 12 by using second driving means
6 tracking adjustment is performed well.

In this embodiment, each tracking adjustment mechanism section can be adjusted independently, thereby making it possible to perform highly granular tracking adjustment.

In addition, when a zoom lens is used as the photographing system, information on longitudinal chromatic aberration that changes as the magnification changes is stored in the storage section.
After the tracking adjustment is performed at a predetermined zoom position, the tracking adjustment may be performed by electrically moving the image sensor along the optical axis to follow the change in magnification based on information from the storage unit.

(Effects of the Invention) According to the present invention, the image sensor provided in the vicinity of the exit surface of the color separation prism is connected to the first image sensor having the above-described configuration. By manually and electrically moving the optical axis using the second drive means, tracking adjustment can be performed easily, quickly, and with high precision, effectively eliminating the negative effects of axial chromatic aberration in the imaging system. Accordingly, it is possible to achieve an imaging device suitable for color television cameras and the like, which is prevented from causing problems.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of the main parts of an embodiment of the present invention applied to a color television camera, FIG. 2 is a detailed view of a portion of FIG. 1 from B view, and FIG. 3 is an explanation from C view of FIG. It is a diagram. In the figure, 1 is a photographic lens, 2 is a filter member, 3 is a color separation prism, 4a, 4b, 4c are tracking adjustment mechanism parts, 5 is an optical base, 6 is a camera base, 7 is a pedestal, and 8 is a fixed base. 9 is a micrometer support plate, 10 is a micrometer, 11 is a top, 12 is a moving base, 13 is a linear bearing, 14 is a piezo element, 15 is an image sensor support plate,
16 is an image sensor, 19 is a drive control circuit, and 101 is an image evaluation circuit.

Claims (2)

[Claims] (1) In an imaging device that separates a light beam from a photographic lens into a plurality of colored light beams via a color separation optical system and then guides the light to each image sensor, at least one of the plurality of image sensors A first driving means for manually moving the image sensor P on the optical axis, a video evaluation circuit that evaluates the video signal from the image sensor P, and moves the image sensor P on the optical axis based on the output signal from the image evaluation circuit. An imaging device characterized by being provided with a second drive means for electrically moving the image. (2) the first driving means utilizes a micrometer;
2. The imaging device according to claim 1, wherein the second driving means utilizes a piezo element.