Color distribution measuring optical system, color distribution measuring apparatus, and color distribution measuring method
AssigneeNikon Corporation
InventorMasatoshi SATO
Life of this patent
Estimating the term…
Abstract
A color distribution measuring optical system generates an image of an object to be measured via an imaging optical system and a color matching function filter. The color matching function filter is an optical multilayer film filter, and the angle of arrangement of the color matching function filter can be changed, with respect to an optical axis of the imaging optical system, depending on the numerical aperture of the imaging optical system by a tilt angle changing device. Various imaging optical systems can be used even when the optical multilayer filter is used.
Claims16
A color distribution measuring optical system which measures a color distribution of a measurement objective via an imaging optical system, the optical system comprising:
- a color matching function filter which is an optical multilayer film filter;
- and
- a changing device which changes an angle of arrangement of the color matching function filter with respect to an optical axis of the imaging optical system.
A color distribution measuring apparatus which measures a color distribution of an objective, the color distribution measuring apparatus comprising:
- an imaging optical system;
- a color matching function filter which has an optical multilayer film;
- a tilt angle regulating device which regulates a tilt angle of the optical multilayer film with respect to an optical axis of the imaging optical system;
- and
- a detector which detects an image formed via the imaging optical system and the color matching function filter.
A color distribution measuring method for measuring a color distribution of a measurement objective based on a luminance distribution of an image of the measurement objective, the color distribution measuring method comprising:
- arranging a color matching function filter having an optical multilayer film on an image side of an imaging optical system;
- regulating an angle of arrangement of the color matching function filter with respect to an optical axis of the imaging optical system depending on an image side numerical aperture of the imaging optical system;
- and
- detecting an image of the measurement objective via the imaging optical system and the color matching function filter in which the angle of arrangement is regulated.
Dependencies are inferred from the claim text.