| 摘要 |
FIELD: measuring equipment.SUBSTANCE: invention belongs to radio measuring equipment and can be used as a broadband measuring instrument of frequency of radio signals. In the acoustic-optic multichannel analyser containing a laser, a collimator, an acoustic-optic deflector, a totally reflecting mirror, two integrating lenses and two lines of photodetectors, in which the measured radio signal is sent to a piezoconverter of the acoustic-optic deflector, and on one of its optical sides the laser radiation falls under Bragg's negative angle and diffracts in the direction of the serially located the first integrating lens and the first line of photodetectors, and on the second optical side of the acoustic-optic deflector the laser radiation, being re-reflected from a totally reflecting mirror, falls under Bragg's positive angle and diffracts in the direction of serially located the second integrating lens and the second line of photodetectors, in addition between the first and second sides of the acoustic-optic deflector and the first and second integrating lenses there is the first and the second polaroids, and the acoustic-optic deflector is executed on the basis of lithium niobate with the slanting angle of cut equal to ?, and the abnormal diffraction characterised by existence of two identical pass-bands ?fand ?fnear different corner frequencies fand f, set by the corresponding size of an angle ?, and connected to each other by means of f-f??f??f, besides, the light length of the piezoconverter and acoustic-optic deflector is chosen from a condition of combination of bands ?fand ?fby the set level of unevenness of diffraction efficiency.EFFECT: expansion of a band of working frequencies.4 dwg |
