Patent ID: 7927472

Claim:
A dielectric multilayer film manufacturing apparatus, the vacuum chamber of which used for the manufacture has a film material source and a reaction source, each arranged alongside to face a rotatable substrate, comprising: a film deposition rate controlling member having an opening that gives a gradient along a radius of the rotating substrate circle to a film deposition rate of the dielectric multilayer film formed on said rotatable substrate; a film thickness correcting member that corrects the film thickness of the dielectric multilayer film formed on said rotatable substrate, the film deposition rate controlling member and the film thickness correcting member being provided between said rotatable substrate and said film material source; light intensity measuring means that measures the intensity of monitoring monochromatic light passing through a plurality of monitoring points along the radius of said rotatable substrate; and a control system that arranges monitoring monochromatic light fluxes of at least one wavelength in ascending or descending order of the wavelengths of the monochromatic light fluxes associated with the positions of the monitoring points along said radius to make the light fluxes pass through the respective monitoring points, and can move said film thickness correcting member in response to a variation of the light intensity measured by said light intensity measuring means.