LASER MEASURING DEVICE

• Main Authors: WATANABE YASUO, EGUCHI KUNIHISA, FUJII SHOICHI, GOMI MITSUO
• Format: Patent
• Language: English
• Published: 07.11.1987
• Subjects: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIRCHEMICAL OR PHYSICAL PROPERTIES; MEASURING; PHYSICS; TESTING

PURPOSE:To obtain a highly accurate anti-Stokes beam by cutting off only the mixed part of a reference laser beam and a Stokes beam, and extracting an anti-Stokes beam contained in the cross-sectional pattern of the remaining beams. CONSTITUTION:A fundamental laser beam omega1 passes through a dichroic mirror 10 and enters into a lens 11 by maintaining its circular cross-sectional pattern. On the other hand, as for a beam omega2, half of the cross-sectional pattern is cut off by a knife edge 13 and it becomes semi-circular, and it is reflected by the mirror 10. The upper part of the beam forms a collinear CARS (Coherent Anti-Stokes Raman Spectroscopy) by the semi-circular beam, and also, the beam omega2 and the lower beam omega1 constitute a minimum cross angle CARS. This collinear CARS is a method which is apt to generate an anti-Stokes beam omega3, therefore, the phase matching adjustment is executed by utilizing the beam omega3 which is generated by this collinear CARS. After an optimum condition has been obtained by this collinear CARS, when the beam omega3 is cut off by a knife edge 14, the beam omega3 which has been generated from a minute intersection on a space which has been generated by the minimum cross angle CARS can be obtained easily.