JPS63132590A - Color camera - Google Patents

Abstract

PURPOSE:To easily and exactly execute a focal adjustment and an adjustment of one-side out-of-focus by sticking a transparent plate to a light emitting surface of a color separation prism and fitting a supporting projecting body projected from a solid-state image pickup element so as to be freely adjustable into a fitting hole provided on the transparent plate. CONSTITUTION:To each light emitting surface 2 of a color separation prism 1, a transparent plate 3 is stuck respectively, and a fitting hole 4 is provided on the outside of an area where an effective luminous flux from a lens of each transparent plate 3 passes through. In the rear of each transparent plate 3, a solid-state image pickup element 5 is placed and from both end parts of the solid-state image pickup element 5 a rod-like supporting projecting body 6 fitted into the fitting hole 4 is projected, and between the supporting projecting body 6 and a hole wall of the fitting hole 4, a sufficient gap is held so that a position of the solid-state image pickup element 5 can be adjusted. In a state that the supporting projecting body 6 is fitted into the fitting hole 4, the color separation prism 1 is fixed to a measuring instrument surface plate, the solid-state image pickup element 5 is held by an adjusting jig and by projecting a reference pattern onto the solid-state image pickup element 5, a position adjustment is executed with regard to a position, a rotation and an inclination in the optical axis direction and the direction vertical to the optical axis. After this adjustment, an adhesive agent 7 is filled and hardened between the hole wall of the fitting hole 4 and the supporting projecting body 6, and the solid-state image pickup element 5 is fixed to an ideal position.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a color camera that uses a color separation prism as a color separation optical system and uses a solid-state image sensor as an imaging means.

[Prior Art] In general, in this type of color camera, the relative positional relationship between the light exit surface of each channel of the one-color separation prism and the light receiving surface of the solid-state image sensor is determined by adjusting the focus for each channel and eliminating one-sided blur. It is necessary to make a decision by taking into consideration the tilt adjustment for the purpose and the registration adjustment between each channel. In order to make such adjustments possible, the color separation prism is fixed on the substrate or housing.
A method has been adopted in which each solid-state imaging device is attached via an adjustable holding mechanism, but this method has the disadvantage that the imaging device itself requires a complicated holding mechanism.

Furthermore, a method is also known in which a solid-state image sensor is bonded to the light exit surface of each channel of a color separation prism using a transparent adhesive. However, with this method, although it is possible to adjust the position and inclination in a plane perpendicular to the optical axis, that is, registration adjustment, it is not possible to adjust the optical axis direction, that is, focus adjustment or one-sided blur adjustment.

Furthermore, as a method to enable adjustment of the optical axis direction, a flexible spacer is interposed between the light exit surface of the color separation prism and the solid-state image sensor, and the adhesive is supported by the spacer. A system in which the deformed state is maintained by curing the adhesive is disclosed in, for example, Japanese Patent Laid-Open No. 58-63279. However, in this case, the linear expansion coefficient of the adhesive is large, so the focus shift due to temperature changes is large.
When a solid-state image pickup device with high resolution is used, there is a problem in that the amount of noise becomes a non-negligible amount. Furthermore, since this method leaves a thick layer of adhesive, there is also the drawback that focus shifts and registration shifts are likely to occur due to changes over time.

[Object of the invention] The object of the present invention is to improve the drawbacks of the conventional example as described above,
A color camera that can easily and accurately adjust the relative positional relationship between the light emitting surface of the color separation prism and the light receiving surface of the solid-state image sensor, and can sufficiently minimize registration and focus shifts due to temperature changes and changes over time. Our goal is to provide the following.

[Summary of the invention] The gist of the present invention is to achieve the above objects.

In a color camera that uses a color separation prism as a color separation optical system and uses a solid-state image pickup device as an imaging means, a transparent plate is attached to the light exit surface of the color separation prism, and an area outside the area through which the effective light beam of the transparent plate passes is provided. Fitting a supporting protrusion protruding from the solid-state imaging device or the solid-state imaging device holder into the provided mounting hole, and maintaining a sufficient gap between the supporting protrusion and the hole wall of the mounting hole; The color camera is characterized in that the gap is filled with a bonding material filled after the position adjustment of the solid-state image sensor to fix the positional relationship between the color separation prism and the solid-state image sensor.

[Embodiments of the invention] The present invention will be explained in detail based on illustrated embodiments.

FIG. 1 is a perspective view showing the relationship between a solid-state image sensor and a color separation prism used in a color camera according to the present invention.
FIG. 2 is a vertical cross-sectional view of each channel in the optical axis direction.A transparent plate 3 is attached to each light exit surface 2 of the zero-color separation prism 1, and the area through which the effective light beam from the lens of each transparent plate 3 passes. A mounting hole 4 is provided on the outside. A solid-state image sensor 5 is arranged behind each transparent plate 3, and rod-shaped supporting protrusions 6 that are fitted into the mounting holes 4 protrude from both ends of the solid-state image sensors 5. A sufficient gap is maintained between the body 6 and the hole wall of the mounting hole 4 so that the position of the solid-state image sensor 5 can be adjusted, and even when the supporting protrusion 6 is fitted into the mounting hole 4, the supporting protrusion 6 remains The body 6 can move freely within the mounting hole 4.

When fixing the solid-state image sensor 5 to the color separation prism 1, the color separation prism 1 is fixed to the measuring instrument surface plate with the supporting protrusion 6 fitted into the mounting hole 4, and the solid-state image sensor 5 is fixed to the measuring instrument surface plate. It is held in an adjustment jig, and the reference pattern is projected onto the solid-state image sensor 5 to adjust the position, rotation, and tilt in the optical axis direction and in the direction perpendicular to the optical axis. After this adjustment, the mounting hole 4 is
By filling the adhesive 7 between the hole wall and the support protrusion 6 and curing it, the solid-state image sensor 5 can be fixed at an ideal position.

FIG. 3 shows another embodiment, in which the shape of the mounting hole 4 provided in the transparent plate 3 is perpendicular to the optical axis direction and the perpendicular line from the optical axis passing through the center of the mounting hole 4. An example is shown in which the support protrusion 6 is fitted into a rectangular shape that is long in the direction, and the support protrusion 6 that is fitted into the rectangular shape is a plate shape that fits into the mounting hole 4. By doing so, the bonding area between the mounting hole 4 and the supporting protrusion 6 can be increased, so that the solid-state image sensor 5 can be fixed more stably.

Further, in the embodiment shown in FIG. 4, the hole wall of the rectangular mounting hole 4 as shown in FIG. An example in which the member 8 is driven is shown. In this case, since the thickness of the adhesive 7 can be reduced, it is possible to minimize adverse effects on image quality such as misregistration of the adhesive 7. Further, by tapering the hole wall on the side away from the optical axis, it is possible to prevent the adhesive 7 from going around.

In each of the above-mentioned embodiments, the adhesive 7 is used to bond the transparent plate 3 and the support protrusion 6, but other bonding materials such as solder may also be used in addition to the adhesive. Of course it's a good thing.

[Effects of the Invention] As explained above, the color camera according to the present invention has the advantage of fixing the relative position 2tfJ between the light emitting surface of each channel of the color separation prism and the light receiving surface of the solid-state image sensor using the conventional method. Focus adjustment and one-sided blur adjustment, which had been considered difficult, can be performed extremely easily and accurately, and it is also possible to perform registration due to temperature changes and changes over time.
Focus deviation can be made sufficiently small, and the solid-state image sensor can be stably fixed to the color separation prism. Furthermore, since these operations can be performed without contacting the light exit surface, there is less risk of damaging the light exit surface.

[Brief explanation of the drawing]

The drawings show an embodiment of a color camera according to the present invention, and the first embodiment shows a color camera according to the present invention.
The figure is a perspective view of a color separation prism and a solid-state image sensor, FIG. 2 is a vertical cross-sectional view of each channel in the optical axis direction, FIG. 3 is a perspective view of another embodiment, and FIG. 4 is a perspective view of yet another embodiment. FIG. 2 is a longitudinal cross-sectional view similar to FIG. 2; Symbol l is a color separation prism, 2 is a light exit surface, 3 is a transparent plate,
4 is a mounting hole, 5 is a solid-state image sensor, 6 is a support protrusion, 7
8 is an adhesive, and 8 is a reinforcing member. Patent applicant Canon Co., Ltd. Figure 2

Claims (1)

[Claims] 1. In a color camera that uses a color separation prism as a color separation optical system and uses a solid-state image sensor as an imaging means,
A transparent plate is attached to the light exit surface of the color separation prism, and a mounting hole provided outside the area through which the effective light beam passes through the transparent plate,
Fitting a supporting protrusion protruding from the solid-state image sensor or the solid-state image sensor holder, maintaining a sufficient gap between the supporting protrusion and the hole wall of the mounting hole, and adjusting the position of the solid-state image sensor. A color camera characterized in that the gap is filled with a bonding material filled later to fix the positional relationship between the color separation prism and the solid-state image sensor. 2. The mounting hole provided in the transparent plate is a rectangle long in the optical axis direction and in a direction perpendicular to the perpendicular line from the optical axis passing through the center of the mounting hole, and the supporting protrusion is formed in the mounting hole. The color camera according to claim 1, which is a plate-like body that fits the holes. 3. The color camera according to claim 2, wherein the hole wall of the mounting hole is tapered, and a wedge-shaped reinforcing member is interposed between the mounting hole and the supporting protrusion.