Abstract: A focus control technique for use in a video camera or the like. An image of an object passes through a focus lens and an electric signal corresponding thereto is formed. High frequency components are extracted from the electric signals to generate estimation values indicative of focus states. A plurality of estimation values that are changed as the focus lens moves are stored in a storage device. A plurality of the stored estimation values are selected and along with the lens positions corresponding to the selected estimation values are used to calculate the just focus position. As a result, even if the estimation value includes noise or the estimation value constantly includes noise when the luminance is low, focus control may be performed with high accuracy. Furthermore, even if the focus lens is passed by the just focus position only once, it is possible to calculate the just focus position. Therefore, the just focus position may be determined at a high speed.

Abstract: A focus control apparatus according to the present invention is a focus control apparatus to be used in a video camera or the like and having imaging means 1, 2 for imaging an object through a focus lens to output an electric signal corresponding to the object, including extracting means 621, 631 for extracting high-frequency components of the electric signals output from the imaging means 1, 2, estimation value generating means 62, 63 for generating estimation values indicative of focus states of the object based on the high-frequency components output from the extracting means 621, 631, a storage means 66 for storing a plurality of estimation values changed as the focus lens is moved in response to a focus lens position in order to obtain a just focus position, a selecting means 4 for selecting a plurality of estimation values to be used for calculation of the just focus position from the estimation values stored in the storage means 66, and a control means 4 for calculating the just focus position based on

Abstract: A focus control circuit (34) which controls the focus of a video camera is provided with a horizontal-direction evaluation value generating circuit (62) which generates a plurality of evaluation values for the horizontal direction, a vertical-direction evaluation value generating circuit (63) which generates a plurality of evaluation values for the vertical direction, and a microcomputer (64) which performs a prescribed operation upon receiving the evaluation values for the horizontal and vertical directions. The circuit (62) generates the evaluation values corresponding to preset evaluation windows of different sizes. The microcomputer (64) selects evaluation values corresponding to an appropriate evaluation window for judging the contrast of an object out of the supplied evaluation values and controls the focus of the video camera based on the selected evaluation values. Therefore, appropriate evaluation values of the object can be obtained.

Abstract: An auto-focus apparatus, a focus adjusting method, an image capturing apparatus and an image capturing method make it possible to perform accurate focus adjustment on a subject for which the focus should be adjusted. The auto-focus apparatus emits an irradiation wave from emitting means for irradiation to a subject while changing an incident angle of the irradiation wave, detects an incident angle of a reflected wave of the irradiation wave reflected by the subject, incident on light receiving means positioned corresponding to the emitting means, determines based on the emitting angle and the incident angle whether or not the subject is a subject for which the focus is adjusted, and adjusts the focus on the subject when determining that the subject is the subject for which the focus should be adjusted, thereby making it possible to accurately adjust the focus on the subject for which the focus should be adjusted.

Abstract: An autofocus apparatus of an imaging apparatus is one having an estimation-value calculating unit for obtaining a plurality of estimation values by using a plurality of areas and a plurality of filters for extracting a horizontal-direction frequency component in a specific image area of a video signal corresponding to a specific image area and supplied from an imaging apparatus for effectively carrying out an autofocus operation of a television camera, a signal processing unit for calculating a control value used for controlling an image pickup lens drive unit of the imaging apparatus in response to an estimation value calculated by the above estimation-value calculating unit, and an output unit for supplying the above control value to the above image pickup lens drive unit.

Abstract: An optical axis correcting apparatus for correcting the optical axes of light beams from a communicating party in an optical space transmission system that transmits and receives the light beams to/from the communicating party, comprises, in order to further accurately correct an optical axis with a simple configuration, optical axis changing means for changing the angle of a reflecting mirror placed in the optical path of the light beam and for changing the optical axis of the light beam to be reflected by the reflecting mirror, optical axis direction detecting means for detecting the direction of the optical axis of the light beam that is changed by the optical axis changing means, optical axis adjusting means for adjusting the angle of the reflecting mirror based on the direction of optical axis of the light beam detected by the optical axis direction detecting means through the optical axis changing means in order to adjust the direction of the optical axis of the light beam toward the communicating party

Abstract: In an optical axis correction device for correcting an optical axis within an optical spatial transmission device, a displacement of focal point can be prevented and a responding speed in rotation of the mirror can be made fast. As the incident light is reflected against the reflection surface of the mirror and radiated against the position sensing sensor, a displacement amount .DELTA.S between the incident point P1 on the position sensing sensor and the reference position P0 is detected at the optical axis correction device. In order to correct the optical axis only by the amount of displacement .DELTA.S, the Y-axis driving mechanism is driven to change an angle of the reflection surface of the mirror. At this time, the position of the reflecting portion on the reflection surface in a direction of Z-axis is prevented from being displaced. For example, a driving force of "-2" is applied to the first Y-axis driving mechanism and concurrently a state of ".+-.0" is held at the second Y-axis driving mechanism.

Abstract: Focus control is provided by estimating an estimation value by extracting a high-frequency component of a video signal for each focus lens position. The correct focus lens position for focusing a target object is determined as that focus lens position where the estimation value for a plurality of conditions at a particular focus lens position becomes maximum. The estimation value is determined to be maximum when, for successive focus lens positions, the estimation value decreases continuously. The various conditions for imaging, according to an aspect of the focus control, includes the filter coefficients for extracting the high-frequency component of the video signal and the size of the windows from which the video signal is imaged.

Abstract: A method, circuit, and apparatus for mitigating effects of wavelength-dependent atmospheric transmission characteristics on an atmospheric optical telecommunication system. The system comprises two atmospheric optical telecommunication units communicating with one another using light propagated through the atmosphere. Each of the atmospheric telecommunication units includes an optical transmitter having a laser generating a transmitted light beam for reception by the other, and an optical receiver. The optical receiver generates an electrical signal in response to a received light beam received from the other of the atmospheric optical telecommunication units. In the method, an increase in noise above a normal noise level is detected in the electrical signal, and a flag signal is generated in response. The increase in noise is due to the received light beam having a wavelength at which the atmosphere has a wavelength-dependent transmission characteristic.

Abstract: An optical atmospheric link device which is adapted to quickly correct the incident position of a light beam with high follow-up accuracy. Incident position detection signals are generated by an optical beam incident position detector in correspondence to the incident position of a first optical beam. The incident position detection signal along with a reference incidence position signal, are utilized to generate incident position correcting signal. The incident position correcting is utilized to move a lens to quickly correct the incident position in a small amplitude mode. Furthermore, a displacement detection signal is generated which corresponds to the displacement of the lens. The displacement detection signal and the incident position correcting signal are utilized to move a pair of mirrors to slowly correct the incident position in a large amplitude mode.

Abstract: An optical atmospheric link system controls the angle an emitted light beam makes to a predetermined direction. A turning force is supplied to a rigid body housing an optical system without direct contact with the rigid body so that changes in the optical axis caused by a disturbance can be compressed, allowing servo-control operation to adjust the optical axis with high speed and with less driving power.

Abstract: In an optical atmospheric communication apparatus for transmitting desired information via an optical beam circulating in the atmosphere, the position of a transmitting object can be easily detected and thus the projecting position of an optical beam can be corrected, even in the case where the optical beam coming from the transmission object cannot be received. The projecting position of the optical beam is displaced within a prescribed range, and the light receiving area of the optical beam reflected at a corner cube reflector is detected in order that the projecting position of the optical beam is corrected based on the centroidal position of the light receiving area.

Abstract: An optical atmospheric link apparatus transmits information data by means of a light beam, an error signal is generated representative of a difference between a direction of a light beam projected from a optical lens means and a direction of a light beam received from a remote transmitter/receiver and a position of a light path of the light beam incident into an optical lens from a light emission means is controlled on the basis of the error signal so that the direction of the light beam projected from the optical lens becomes coincident with the direction of the light beam received from the remote transmitter/receiver.

Abstract: An optical communication system which does not require a re-adjusting operation of an irradiating direction of a light beam and is improved in convenience in use. The optical communication system includes first and second terminals remotely located from each other for transmitting therebetween a light beam carrying an information signal therein. A first light beam having a predetermined direction of polarization is generated in the first terminal and transmitted to the second terminal by way of an optical system while a second light beam having a different direction of polarization comes from the second terminal and is received by way of the optical system. A beam selector passes one of the first and second light beams and reflects the other light beam. An electric signal is generated in response to the received second light beam, and the direction of the first light beam is controlled in response to such electric signal.

Abstract: A wave combining apparatus for semiconductor lasers includes first and second dichroic mirrors for combining laser beams having the same direction of oscillation by waveform division, respectively, and a polarizing beam splitter prism for combining the first and second resultant beams into a single, combined waveform.

Abstract: In an optical atmospheric link system for transmitting a light beam carrying an information signal between a transmitter and a receiver which is located apart from the transmitter, the transmitter includes a light source for generating the first light beam modulated with the information signal, a first optical system for transmitting the light beam toward the receiver, a second optical system for turning at least a portion of the light beam, and a third optical system for observing the light beam turned by the second optical system and the receiver.

Abstract: An optical space transmission apparatus for use in conjunction with an optical space transmission line (8) for carrying transmission light and reception light comprising an information transmission light emitting element (5) for generating transmission light, an optical transmission system (6,7) including an optical transmission fiber (7), an information reception light receiving element (9) for detecting reception light, an optical reception system (4), and a transmission/reception common lens (3) which is optically coupled to said optical space transmission line (8), characterized in that an end portion (7a) of said optical transmission fiber (7) is positioned near the focal plane of said transmission/reception common lens (3) and near, or on its optical axis, the transmission light emitting from said information transmission light emitting element (5) is transmitted into the optical space transmission line (8) through said optical transmission system (6,7) and through said transmission/reception common len

Abstract: A laser beam soldering apparatus is provided for soldering parts, such as, lead wires provided for an IC chip which are arranged closely to each other. The apparatus includes a plurality of laser beam irradiation units employing a semiconductor laser and a mounting dish for mounting the irradiation units. The dish has a plurality through holes for receiving the irradiation units. The irradiation units are mounted in the plate so as to be directed to one focal point to form a desired beam spot shape. A small beam spot having sufficient heat for soldering is thereby obtained.

Abstract: A dielectric rotary coupler for electromagnetic waves of the microwave frequency region structured of a substantially ring-shaped rotary member and a stationary member, each member being formed of a dielectric waveguide, or line, having a rectangular cross-section. The rotary line and the stationary line are arranged to face each other with a predetermined space therebetween along a coupling length, through which a microwave, for example, a carrier microwave FM-modulated by a signal reproduced by a rotary head of a VTR, is coupled from the rotary line to the stationary line, or vice versa.

Abstract: An automatic ground softening apparatus for crushing underground earth layer into pieces by blowing out compressed air from tips of air nozzle pipes driven deep into the ground at several positions at a time, is mounted on the load-carrying platform of a truck. The automatic ground softening apparatus includes a plurality of piston-cylinder assemblies mounted on the truck's load-carrying platform at different positions thereof. The air nozzle pipes each depend from the lower end of the piston rod of each of the piston-cylinder assemblies. Some or all of the piston-cylinder assemblies are operable through centralized control by operating an operating panel provided aside a driver's seat in the truck. The depth of driving of each air nozzle pipe driven by each piston-cylinder assembly into the ground and the pressure of compressed air jet from the tip nozzle of the air nozzle pipe into the earth can be set to desired values by operating the operating panel.