Abstract: In this invention there is disclosed a color image reader being able to read in three modes, a black and white mode, a color mode and a dropped color mode. The reader includesthree fluorescence lamps for illuminating a document to be read, each lamp having their own peaks in red, green and blue light zones respectively,an optical system for obtaining a real image of the document therethrough,a single image sensor being arranged at the position where the real image is focused,a mode selection device for choosing one mode from the three modes anda control device for lighting every fluorescence lamp in such a manner that three fluorescence lamps are turned on and off sequentially and successively when the color mode is chosen and, when the black and white mode is chosen, all of them are turned on at the same time.

Abstract: In this invention, the spectral structure of the high-frequency current generated by the cauterizing power circuit for high-frequency incision and excision tools is set in the frequency interleave relationship with the comb-shaped spectral structure inherent in the picture signal formed by the solid pickup element, when an affected part of a subject is collected using the high-frequency incision and excision tools together with an endoscope with the solid pickup element. The picture signal, output form the solid pickup element, is supplied to the display unit via a comb line with the characteristics to meet its spectral structure to become the signal without the spectrum component (noise) caused by the high-frequency current from the said cauterizing power circuit.

Abstract: Methods for improving the availability of information derived from signals received from an object irradiated with coherent pulses of any form of radiation that exhibits a wave nature are disclosed. A method for reducing speckle derives separate component noncoherent signals from the received signals, and combines these separate noncoherent signals to form improved composite noncoherent signals. Weighting and processing of component signals can be applied as a function of time, frequency, and signal amplitude to optimize speckle reduction in all or a critical part of the signal by compensating for the range and frequency dependence of attenuation and the frequency dependence of scattering phenomena. In a method for enhancing resolution, separate component coherent signals are derived from the received signals, weighted and processed, and combined to form improved composite coherent signals; then noncoherent signals are derived from the improved composite coherent signals.