ALIGNING METHOD, POINT DIFFRACTION INTERFERENCE MEASURING INSTRUMENT, AND HIGH-ACCURACY PROJECTION LENS MANUFACTURING METHOD USING THE SAME INSTRUMENT

摘要

PROBLEM TO BE SOLVED: To provide a PDI(point diffraction interferometry)-type interference measuring instrument etc., allowing the alignment of a tested surface with the interference measuring instrument by using a simple procedure. SOLUTION: This aligning method is used in a measuring method for measuring the optical characteristics of a tested object 104 by causing measuring light to interfere with reference light and detecting a phase difference. The measuring light is one of two light beams into which light generated from point light source generating means 101, 102, and 103 is separated after it is passed through the tested object 104. The reference light is a spherical wave generated by passing the other beam through a minute transmission part 106a. This aligning method is used to align the other beam with the transmission part 106a and has a process for disposing a first reflection member 112 (215) in the proximity of a condensing point CP conjugated with the transmission part 106a and formed by the light transmitted by the tested object 104, and a process for detecting vertex reflected light from the reflection member 112 to adjust the position of the reflection member 112 in the optical axis direction based on reflected light information.