DEVICE FOR BIREFRIGENCE MEASUREMENT Russian patent published in 1995 - IPC

FIELD: polarization-optical investigations. SUBSTANCE: device can also be used for contactless check of elastic stresses in isotropic materials. Device includes monochromatic radiation source 1 which radiation passing through light beam stretcher 2, polarizer 3 and phase quarter-wavelength plate 4 is focused on to sample 7 with the aid of microlens. Sample 7 is put on two-coordinate scanning gear 6. Radiation passed through sample 7 is directed by means of collecting lens 8 through rotary analyzer 9 to photodetector 11 and from the latter to input of selective amplifier 13 tuned to double rotation speed of analyzer 9. Voltage from line output of amplifier 13 is fed to input of register 14. Alternating voltage from amplifying output of amplifier 13 goes to input of phase difference meter 15 to which input reference voltage is supplied from unit 10 of formation of reference signal of optron pair with disc interrupter anchored on rotary analyzer 9. Output voltage of phase difference meter 12 proportional to angle of deviation of major axis of polarization ellipse of radiation passed through sample 7 from axis of polarizer 3 is fed to input of register 16. EFFECT: expanded application field and provision for determination of axes of birefringence. 2 cl, 1 dwg