Abstract: A laser processing apparatus including a laser oscillator, a beam expander, and a light converging system. An output-end-side optical component formed by the beam expander and the light converging system includes one light converging system having composite characteristics of the optical component and the light converging system. Accordingly, the number of lenses used is reduced, the absorption loss of the laser output is lowered, and the number of parts used is reduced. Also disclosed is a laser processing apparatus in which an optical component forming a beam expander is formed partially of an output coupling mirror of the laser oscillator, whereby the number of lenses used is reduced.

Abstract: A digital signal processing apparatus is shown which is applicable for real time operation in the power spectrum of the detected outputs of ultrasonic Doppler blood flowmeter. The apparatus comprises a digital operating means, a memory means which is connected to said digital operating means to transfer data thereto and receive data therefrom, a fixed instruction generating portion for generating operating code for the digital operating means and addresses for the memory means, a read only memory for storing data of a squaring operation which has address inputs at the bit position selected as most suitable from the input data bus line of said digital operating means, an overflow detecting means when input data exceeds the region of the address input, and digital saturation circuit, whereby the power spectrum can be calculated by fundamental algorithm of WFTA having a smaller number of operating steps than algorithm FFT.

Abstract: Ultrasonic echo signals are detected in phase and integrated with a period corresponding to an ultrasonic pulse. The integrated values are sampled and the difference between two integrated values is successively frequency-analyzed.

Abstract: A light deflector utilizing the anisotropic Bragg diffraction in an anisotropic medium in which the directions of the wave front normal and the energy propagation of ultrasonic waves are arranged to be different and the frequency range of the ultrasonic wave for causing re-diffraction of light diffracted once by said ultrasonic wave is set outside the driving frequency range. The diffraction efficiency does not fall near the central frequency of the driving ultrasonic frequency range due to the prevention of rediffraction. Further, the driving frequency can be selected over a remarkably wide range compared to that of the conventional light deflector.