초록 ▼

An optical low-pass filter is built with circular phase components consisting of randomly distributed convex and concave surfaces. The area of the phase components is structured to cover 1/2the entire surface area of the low-pass filter. Moreover, the phase components are set to a height such that t

An optical low-pass filter is built with circular phase components consisting of randomly distributed convex and concave surfaces. The area of the phase components is structured to cover 1/2the entire surface area of the low-pass filter. Moreover, the phase components are set to a height such that the phase difference between the light passing through the phase components and the other areas of the filter is 1/2its wavelength. The optical low-pass filter is installed in front of the photometric optical system. It is therefore possible to precisely measure light regardless of incidence of light from the photographic subject even when using photometric sensors that have been divided into multiple units.

대표청구항 ▼

A camera comprising: a photographic image forming lens that forms a first composed image from light rays passing therethrough from a photographic subject; a finder screen disposed adjacent the photographic image forming lens on which the first composed image of the photographic subject is formed; an

A camera comprising: a photographic image forming lens that forms a first composed image from light rays passing therethrough from a photographic subject; a finder screen disposed adjacent the photographic image forming lens on which the first composed image of the photographic subject is formed; an optical low-pass filter that filters a high frequency component of light from the first composed image for accurate measurement of light, said optical low-pass filter being disposed adjacent to and downstream from the finder screen, said optical low-pass filter comprising a plurality of phase components randomly arranged on a flat surface to prevent generation of interference patterns of light; a photometric image forming lens that forms a photometric image of the photographic subject from the filtered light from the optical low-pass filter, said photometric image forming lens being disposed downstream from said optical low-pass filter such that light passes through said photometric image forming lens to form a second composed image; and a photometric sensor disposed substantially at a point where the second composed image is formed that measures light from the second composed image in order to determine light exposure for the photographic subject, wherein the phase components have a diameter D defined by D≤ll