Displacement measurement apparatus, non-contact input apparatus, and biological micromotion measurement apparatus

Abstract

A displacement measurement apparatus includes: a light emitter to emit coherent light to an object; a light position detector to detect an instantaneous intensity variation of an interference image of the object; and an interference imaging forming unit disposed between the object and the light position detector along an optical path of reflection light reflected from the object. The interference imaging forming unit forms the interference image with the reflection light reflected from the object and magnifies a point spread function of an optical system to magnify a size of a speckle particle of the interference image.

Dependencies are inferred from the claim text.