| 摘要 |
PURPOSE:To prevent flare ghosts owing to reflection of diagonal luminous fluxes in an optical low-pass filter of a single tube type colar camera, by providing a light absorbing layer on the side face of an optical anisotropic crystal constituting the filter. CONSTITUTION:In a single tube type color camera, the image of a subject by an imaging optical system 2 is formed on the photoelectric surface of an image pickup tube 2 by way of a birefringent plate of crystal or the like and a stripe filter 4 for color separation. Normal light and extraordinary light are spacially separated by the plate 3 and space frequency filter characteristics are shown. A light absorbent 10 is coated on the side face 6 parallel to the optical axis 1 of the plate 3, and a diagonal luminous flux 9 is scattered and absorbed by the pigments contained in the absorbent 10, whereby flare ghosts are prevented. The carbon vacuum deposited or sputtered on a satin surface is used as the absorbent. In addition, stray light is suppressed more by the absorbent of a refractive index close to that of the plate 3. |
