| 摘要 |
PROBLEM TO BE SOLVED: To improve the spatial resolution in the direction of optical axis to achieve high sensitivity and high spatial resolution when measuring the cross sectional image of a measuring sample. SOLUTION: This device for measuring the cross sectional image of a measuring sample is provided with a light source 1, the measuring sample 5 irradiated with light waves from the light source 1 coming through a beam splitter 3 and an objective lens 4, a one-dimensional array light detector 10 and a signal processor 13. Signal light 21 which is back scattering light from the sample 5 enters the detector 10 through the objective lens 4, the beam splitter 3 and a biprism 9 and reference beam 22 enters the detector 10 through mirrors 7, 8 and the biprism 9 after passing through the beam splitter 3 and a phase modulator 6 for heterodyne detection to generate a spatial interference intensity pattern by an angle 2θformed by the signal light 21 and the reference beam 22. The processor 13 changes the spatial interference intensity pattern with modulation frequency (f) of the phase modulator 6 with respect to time and has a memory for storing the spatial interference intensity pattern as one-dimensional distribution of beam amplitude. A space interference intensity value is raised to the N-th power, and whole amplitude of its half value is narrowed to substantially N-1/2 to improve the spatial resolution in the direction of optical axis.
|
