Patent ID: 8497991

Claim:
A thin-film inspection apparatus, comprising: a light source that radiates single-wavelength light to an inspection-target substrate, which is formed by forming a thin film on a glass substrate from the glass substrate side; a light receiving section that is disposed such that a light receiving axis intersects with an optical axis of illumination light emitted from the light source at a predetermined inclination angle and that receives diffused transmitted light that has been transmitted through the inspection-target substrate; and a processor that obtains a haze ratio of the thin film on the basis of an intensity of light received by the light receiving section, wherein the processor has a haze ratio characteristic that is made by associating the haze ratio and the light intensity of the diffused transmitted light and obtains the haze ratio by using the haze ratio characteristic and the intensity of the light received by the light receiving section, and wherein in a case where a plurality of test pieces, which is formed by forming thin films having different haze ratios on glass substrates, is provided; the diffused transmitted light when the test piece is shifted vertically by a predetermined amount in an optical axial direction of the illumination light is received by the light receiving section; and the haze ratio characteristic is made by associating the light intensity and the haze ratio, the light receiving section is disposed at an inclination angle such that a relationship between the haze ratio and the light intensity is expressed as a monotonic increase or a monotonic decrease within a range of the haze ratios of the thin film to be inspected, and a maximum value of an amount of change in the light intensity due to a vertical shift of a mounting position of the test piece becomes a predetermined value or less.