Abstract: A stereoscopic endoscope comprises an objective lens array having one optical axis, a relay lens array for transmitting an object image produced by the objective lens array, a pupil split element that is located at an entrance pupil position of the relay lens array; that is, a position at which the relay lens array forms an entrance pupil, a position near the entrance pupil position, or a position conjugate with those positions, and that splits an entrance pupil formed by the relay lens array into a plurality of portions, an image formation optical system that receives a beam emanating from the relay lens array and forms a plurality of object images in cooperation with the pupil split element, and imaging devices for receiving the object images.

Abstract: Metallic alloy parts which contain easily oxidizable metallic elements, are welded without solder by applying a non-deliquescent flux thereto at a negligible amount and subjecting them to a high temperature under an inert and non-explosive atmosphere.

Abstract: A stereo endoscope according to the present invention includes a pair of objective optical systems, a pair of relay optical systems, an imagery optical system having a single optical axis, and a pair of imaging devices. The imagery optical system is a zoom optical system or a varifocal optical system. For example, an encoder is used to detect a magnitude of moving lenses in the zoom optical system. Based on the detected magnitude, a control unit allows the two imaging devices to approach or depart from each other. Thus, the stereo endoscope attains the coincidence between observation points of right and left fields of view against the displacements of display points of right and left object images resulting from variations of zooming magnifications.

Abstract: A coding and decoding apparatus for an acoustic signal obtained by extracting a series of sampled acoustic signal data as a series of frames. From data obtained over each of a predetermined number of discrete frequencies by implementing orthogonal transform processing to acoustic signal data using the same window function for first and second frames in sequential frames of the acoustic signal having a predetermined fixed time length, phase information for each of the discrete frequencies is obtained for every first and second frames. Then, quantities of changes in the phase information of each one of the discrete frequencies in the first frame with respect to the corresponding frequencies in the second frame are determined.

Abstract: An objective lens system for endoscopes comprising, in order from the object side, a first lens component having negative refractive power, a second lens component having positive refractive power and a third lens component having positive refractive power; wherein astigmatism is corrected favorably by using an aspherical surface in the third lens component or an aperture stop is arranged between the second lens component and an image surface of the objective lens system, and aberrations including chromatic aberration are corrected favorably.

Abstract: The measuring endoscope includes a device for producing interference fringes, a device for projecting the interference fringes onto a surface of an object to be measured, a device for scanning the interference fringes, an imaging device for reading vibrations of brightness on the surface of the object to be measured which are caused by the scanning of the interference fringes and a processing device capable of determining depths of concavities and heights of convexities on the surface the measured object by calculating data output from the imaging device. This measuring endoscope makes it possible to determine accurately the location of internal diseases within organs of human bodies, defects in gas pipes and so on.

Abstract: By data every a predetermined number of discrete frequencies obtained by implementing orthogonal transform processing to acoustic signal data by using the same window function for first and second frames in sequential frames of an acoustic signal having a predetermined fixed time length, phase information every respective discrete frequencies are obtained every the first and second frames. Then, quantities of changes of phase information every discrete frequencies corresponding to each other in the first and second frames are determined. On the assumption that the quantities of changes of phase information every individual discrete frequencies are fixed on the time base, individual phase information every a predetermined number of discrete frequencies in a frame at a third time position existing at a time position of a multiple of integer of a time difference between the first and second time positions are determined to predict phase information of the frame at the third time position.

Abstract: This invention discloses a heterojunction type field effect transistor such as 2DEG-FET and a heterojunction type bipolar transistor such as 2DEG-HBT. The former is fabricated by applying to the formation of its source and drain regions a technique which causes the disorder of the heterojunction by intoduction of an impurity such as by ion implantation or a technique which causes the disorder of the heterojunction by forming a film made of at least one kind of material selected from insulators, metals and semiconductors which have a different linear coefficient of thermal expansion from that of the material of a semiconductor substrate on the heterojunction semiconductor region which is to be disordered. The latter is fabricated by applying either of the techniques described above to a base ohmic contact region. These semiconductor devices can reduce the source-gate resistance and the parasitic base resistance.

Abstract: A waveform equalizer for reducing distortion of a digital signal produced from a digital data recording and playback system or transmission system is formed of a neural network having fixed weighting coefficients. Respective values for the coefficients are established by generating a corresponding simulated neuron network, by software implementation using a computer, and by executing a neuron network learning operation using input values obtained from a distorted digital signal and teaching values obtained from an original digital signal which resulted in the distorted digital signal.

Abstract: A photo-pulse from a photo-pulse generating apparatus is branched, where one branch is radiated to an examined body and the reflected light reflected within the examined body is delayed in time in proportion to the depth from the surface of the examined body and is led to a time-analyzing reflected light measuring apparatus. In this measuring apparatus, the other branched reference photo-pulse or reference signal pulse is input as delayed by the time for which the photo-pulse reflected within the examined body returns and only the reflected light component synchronized with the entering timing of this reference light pulse is analyzed in the time and is detected. By varying the detection sensitivity of this measuring apparatus in response to the depth from the surface of the examined body, the interior can be observed.

Abstract: A display having a diffraction grating pattern includes:(a) a flat substrate; and(b) at least one dot formed on a surface of the flat substrate, the dot being formed by a diffraction grating pattern as an aggregate of a plurality of curves obtained by translating a curve.

Abstract: A hetero junction bipolar transistor provides a contact area an area between an emitter (or collector) electrode and a wiring formed on the electrode that is larger than that of the emitter (or collector). A variation in voltage applied to an emitter (or collector)-base junctions is prevented and a stable operation of the transistor is attained. In addition, when an etching operation is carried out, an insulation film is formed on a side part of a mask. A patterning of the emitter (or collector) is then carried out and thus an emitter (or collector) having a size approximate to that of the mask is formed.

Abstract: An image scanner is comprised of a light source for illuminating an original document, an image sensor for receiving a reflected light from the original document and converting the same into an output signal of image data, a device for relatively moving the original document and the image sensor, an iris mechanism provided on an optical path between the original document and the image sensor, a reference reflection plane provided such that a light from the light source is reflected and the reflection light becomes incident on the image sensor, a comparing circuit for comparing a level of an output signal from the image sensor with a reference level when the image sensor receives the light from the reference reflection plane, and a device for correcting a dynamic range of the image scanner by controlling the iris mechanism on the basis of the compared output.

Abstract: An identification mark comprises a set of a plurality of mark elements. One mark element is divided into a large number of first and second fine square regions alternately arranged. One or two basic gratings selected from a plurality of types of basic gratings is/are drawn in both fine square regions, so that patterns are formed. Since the basic gratings are different in direction of the grating or spatial frequency, the types of the basic gratings are different from each other. One selected type of basic gratings is drawn in all first fine square regions. Similarly, the one or another type of basic gratings is drawn in all second fine square regions. At least one first fine region and at least one second fine region exist in the diameter of the light beam when light is radiated on the mark element for optical read. Thereby, types of patterns, which one mark element can obtain, are increased.

Abstract: In a thermal fixing device, a roller having a heat generating element includes a heating and cooling unit which is made up of a cooling device which serves also as a support, and a heat generating device with a PTC thermistor heater element as a heat source so that an endless metal belt which is turned while being in contact with the heating and cooling is heated on the transfer sheet inlet side and cooled on the transfer sheet outlet side. Thus, the toner on a transfer sheet which is not fixed yet is heated to higher than the melting point on the transfer sheet inlet side so as to be molten and permeated in the transfer sheet, and cooled on the transfer sheet outlet side, and then separated from the metal belt. The surface of the metal belt is covered with lubricative resin, to prevent the occurrence of low temperature offset or high temperate offset, with a result that the fixing operation is stable at all times.

Abstract: This invention discloses a heterojunction type field effect transistor such as 2DEG-FET and a heterojunction type bipolar transistor such as 2DEG-HBT. The former is fabricated by applying to the formation of its source and drain regions a technique which causes the disorder of the heterojunction by introduction of an impurity such as by ion implantation or a technique which causes the disorder of the heterojunction by forming a film made of at least one kind of material selected from insulators, metals and semiconductors which have a different linear coefficient of thermal expansion from that of the material of a semiconductor substrate on the heterojunction semiconductor region which is to be disordered. The latter is fabricated by applying either of the techniques described above to a base ohmic contact region. These semiconductor devices can reduce the source-gate resistance and the parasitic base resistance.

Abstract: A process control apparatus and a process control system for observing the waveform of the deviation between a set point which controls the process in a control loop and the process controlled variable transmitted from the process so that the operating parameters are adjusted in accordance with a predetermined adjustment rule by using the deviation based upon the absolute value of a wave for every half cycle of the wave. Therefore, even if the process controlled variable is influenced, the area of the wave cannot be changed significantly. As a result, the operating parameters can be adjusted correctly, causing the process controlled variable to quickly coincide with the set point.

Abstract: In order to have metallic articles to be brazed preheated evenly as a whole before transferring them into a brazing chamber of a continuous furnace where a high brazing temperature is created, a difference of temperatures of parts of the articles during their preheating is remotely sensed by means of their infrared energies and is minimized as small as possible by changing a transfer speed of the articles during their preheating with reference to the information based upon the infrared energies then sensed. A brazing period of time in the brazing chamber is kept constant and short, irrespectively of the transfer speed of the articles.

Abstract: An optical low-pass filter comprising at least two boundary surfaces arranged substantially parallel to each other which can split incident light into two components or reflect it and at least one of which has color dependency, in order to make it possible to be favorably used to an objective optical system for for endoscopes, to have wavelength dependency to response, and to minimize the generation of color moire. The optical low-pass filter is constructed in the form of various shaped prisms and can also have two-dimensional filter characteristics.

Abstract: A novel fluoride flux with Li ions which is extermely insoluble to water and thus noncorrosive, and which is excellent especially for use with the brazing of articles made of aluminum alloys containing Mg. A novel method for preparing such fluoride flux by a dry process is also described.