Illumination optical system for image pickup apparatus

摘要

An illumination optical system for an image pickup apparatus includes a plurality of light sources arranged in a circular loop pattern and a prism plate shaped like a circular loop. the prism plate includes a prism surface at which illumination light from the light sources enters and on which a plurality of prism columns arranged in a circular loop pattern in a circumference direction of the prism plate are formed and an outgoing surface from which the illumination light is emitted. the prism surface includes a flat portion on at least one of a peak formed by each of the plurality of prism columns and a trough formed between the plurality of prism columns. the flat portion is substantially parallel to a tangential direction of the prism plate.

主权项

1. An illumination optical system for an image pickup apparatus, the illumination optical system comprising:
a plurality of light sources arranged in a circular loop pattern; and a prism plate shaped like a circular loop, wherein the prism plate includes
a prism surface at which illumination light from the light sources enters and on which a plurality of prism columns arranged in a circular loop pattern in a circumference direction of the prism plate are formed, andan outgoing surface from which the illumination light is emitted, wherein the plurality of prism columns are each extended in a radial direction of the prism plate, wherein the prism surface includes
a flat portion on at least one of a peak formed by each of the plurality of prism columns and a trough formed between the plurality of prism columns, the flat portion being substantially parallel to a tangential direction of the prism plate.