SU667940A1 - Acoustooptic filter - Google Patents

Description

one

The invention relates to optical instrumentation, in particular to the field of spectrometry, and can be used in the development of optical spectral instruments.

An acousto-optic filter is known that contains a polarizer, an X-CP quartz acoustic duct, an ultrasonic longitudinal wave transducer, and an analyzer 1.

The disadvantage of this design is its operation on. the reflection, when the light beam first propagates along the direction of propagation of the ultrasonic wave and, reflected from the transducer, against this direction. The result of this mode is that it is in principle impossible to obtain a transmittance greater than 50%.

The closest technical solution to the present invention is an acousto-optic filter containing a light-sound conductor, a trihedral prism made of an isotropic material with a metal mirror applied to its large face and an ultrasonic transducer 2.

The presence of a prism with a metal mirror applied by Tia ensures that the device operates in a per-pass mode and, accordingly, achieves the maximum transmittance of the filter.

The disadvantage of this device is amplitude-phase distortion over the aperture of the filtered optical wave. This disadvantage is detected at large input apertures, where the different length of the acousto-acoustic interaction leads to a significant non-uniformity of the transmittance fshtra, i.e. to the amplitude-phase distortion of the aperture of the filtered light beam.

five

The aim of the invention is to eliminate amplitude-phase distortion over the aperture of the filtered light wave.

Claims (2)

This is achieved by the fact that in the proposed filter the output face of the light and sound conductor is perpendicular to the optical axis of the device, and a second triangular rectangular prism from an isotropic ma is placed between the light sound guide and the three-edged prism. .% v of the material, connected to the light and sound of the waveguide with its small edge. The drawing shows the described acousto-optic filter. The filter contains a polarizer 1, a light-sound conduit 2, triangular prisms 3 and 4 of isotropic material, a metal mirror 5 applied to a large edge of one of the prisms, an ultrasonic transducer 6 applied to a small side face of the prism 4, an analyzer 7. The incident light beam passes the floor The transducer 1 enters through the entrance face of the light-acoustic conduit 2 into the region of acousto-optic interaction, where as a result of the collinear interaction with the ultrasonic wave, the polarization plane of the linearly polarized input is rotated. Puig-stand at 90 °. Proceeding through a three-sided prism 3 and reflecting from a metal mirror 5, a ray of light with orthogonal polarization passes a squared crossed polaroid 7. Due to the presence of an additional three-sided prism of isotropic material, the output side of the light-acoustic circuit is perpendicular to the axis of the device, which ensures the the length of the acousto-optic interaction throughout the apertz of the light wave and. / four ,.;:::;;::--;-:..".:. K to corollary, the elimination of amplitude-phase distortion by the aperture of the optical wave. Claims of the invention: A light optic containing light-acoustic conductor, a triangular rectangular prism made of tropic material with a metal mirror applied to its large face, and an ultrasonic transducer, characterized in that, to eliminate the light-phase distortions along the aperture of the filtered optical wave, the output face of the light beam is perpendicular to the optical axis of the device, and between the light guide and said prism there is a second triangular rectangular prism of isotropic material material connected to the light and sound conduit with its small edge. Sources of information taken into account in the examination {. R.W. Acoustic diffnaction oi EiVbt In umrotnopio rnedioi- DEEE Toiirr. QE-3, 2, 85, 1967. 2. US patent No. 2982818, cl. 350-149, 1976., / 7y v cSema