JPH0731201Y2 - Color camera - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a color television camera using a color separation prism as color separation optics.

Conventionally, one side of the color separation prism is adhesively fixed to the prism base. A color separation prism having three or more blocks has at least one parallel air gear, and the two blocks are separated by the air gear, and the color separation prism is formed by fixing them on the prism base. ing. However, when the temperature is changed, the parallelism of the air gear cannot be maintained, and the air gear changes in a wedge shape, which causes a registration race error.

Also, in a color separation prism formed by two blocks, the dichroic mirror is sandwiched between the blocks, and the bonding is performed. However, the bonding strength of the dichroic mirror is lower than that of glass comrades. The temperature change causes a wedge-shaped change, which causes a registration race error.

In particular, in a color television camera using a solid-state image sensor and having no registration ratio adjusting mechanism, a registration position error due to a temperature change may be a problem. In order to maintain the parallelism of the air gear, iron, titanium, ceramics, etc. with a small coefficient of linear expansion are adhered to the side surface opposite to the side where the prism base is adhered. Therefore, it is difficult to suppress the registration race error due to the temperature change.

In addition, these members generally have poor workability and high material cost, resulting in cost up.

In order to solve the above problems, the present invention has a problem that a color separation prism in which a plurality of prisms are combined causes a registration resolution error when the prisms move with each other, and the plurality of prisms are integrated into a small amount. When moving, each channel moves by the same amount, so it is noted that it does not appear as a registration race error.

Therefore, in a color camera using a color separation prism composed of at least three glass blocks, one side surface of the color separation prism is adhered and fixed by a prism base, while the three glass surfaces are opposite to the one side surface. The side surface including all blocks is adhesively fixed by a glass plate.

FIG. 1 is a perspective view of a color separation prism applied to the color camera of the present invention. FIG. 2 is a cross-sectional view of FIG. The color separation prisms 11, 12, 13 are integrally fixed to a predetermined position on the glass plate 3. A hard adhesive such as an epoxy adhesive can be used for this fixing. Further, the fixing to the prism base 2 may be performed by positioning the color separation prisms 11, 12 and 13 before the glass plate 3 is integrally fixed so as to position the prisms relative to each other. In the color separation prism fixed integrally with the glass plate, the positional relationship between the prisms does not change due to temperature changes, so the color channels only make the same small amount of movement, and no registration resolution error occurs. is there. To reduce the registration error,
If the glass plate 3 is made of the same glass material as the color separation prism 1, the difference in linear expansion can be made zero, which is preferable.

Furthermore, when the method of interposing a glass plate between the color separation prism and the prism base is combined as proposed by the applicant in order to reduce the registration race error,
Furthermore, the color separation prism can be integrated, which is preferable. or,
By this method, the restriction on the position where the prism base is attached is eliminated, and at the same time, the restriction on the fixing means of the integrated prism is greatly relaxed.

As described above, the color camera of the present invention can suppress the registration race error due to temperature change, which has been difficult in the past, with sufficient accuracy. The combination of the color separation prism and the method in which a glass plate is interposed between the prism base and the color separation prism ideally suppresses the registration resolution error and ideally integrates the color separation prism. The restrictions on the means of fixing will be greatly relaxed.

[Brief description of drawings]

FIG. 1 is a perspective view of a color separation prism applied to the color camera of the present invention. FIG. 2 is a cross-sectional view of FIG. 1 ... Color separation prism 2 ... Prism base 3 ... Glass plate 11 ... Color separation prism 1st block 12 ... Color separation prism 2nd block 13 ... Color separation prism 3rd block

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication H04N 9/097

Claims (2)

[Scope of utility model registration request] 1. A color camera using a color separation prism composed of at least three glass blocks,
A color camera, wherein one side surface of the color separation prism is adhesively fixed by a prism base, and a side surface including all of the three glass blocks is adhesively fixed by a glass plate on the opposite side of the one side surface. 2. The color camera according to claim 1, wherein the glass plate is made of the same material as the color separation prism.