Abstract: A surveying machine that automatically adjusts an optical axis includes a sighting optical system for sighting an object, a light-transmitting optical system that transmits a beam for surveying, radiated from a light source, to the object, a deviation detector, and an optical axis adjuster. The deviation detector detects a deviation between a first optical axis corresponding to the sighting optical system and a second optical axis corresponding to the light-transmitting optical system. The optical axis adjuster automatically adjusts at least one of the first optical axis and the second optical axis so as to correct the deviation.

Abstract: A surveying machine that automatically adjusts an optical axis includes a sighting optical system for sighting an object, a light-transmitting optical system that transmits a beam for surveying, radiated from a light source, to the object, a deviation detector, and an optical axis adjuster. The deviation detector detects a deviation between a first optical axis corresponding to the sighting optical system and a second optical axis corresponding to the light-transmitting optical system. The optical axis adjuster automatically adjusts at least one of the first optical axis and the second optical axis so as to correct the deviation.

Abstract: An autofocus distance-measuring optical system includes a sighting telescope having an objective lens for sighting an object; an optical distance meter which includes a light-transmitting optical system for transmitting a measuring light via the, and a light-receiving optical system for receiving light reflected by the object; a focus detecting device for detecting a focus state of the sighting telescope; and a controller for controlling the sighting telescope to automatically focus on the object in accordance with the focus state detected by the focus detecting device. The focus detecting device is a phase-difference detection type which detects an in-focus state from a pair of images respectively formed by two light bundles which are passed through two different pupil areas. The two different pupil areas are positioned so as not to interfere with any optical elements of the optical distance meter.

Abstract: Disclosed is an integral transmitter-receiver optical communication apparatus, including: a transmitter-receiver device which includes: a transmitter having a laser source for emitting a laser beam modulated in accordance with a transmission information signal, a receiver having a position detecting sensor and a light receiving element which receive a complementing modulated laser beam transmitted from a complementing transmitter, and a beam splitting device for splitting the modulated laser beam and the complementing modulated laser beam which are incident thereon as two separate laser beams; a telescopic optical system for transmitting the modulated laser beam emitted by the laser source and for receiving the complementing modulated laser beam transmitted from the complementing transmitter; and a light beam deflecting device positioned between the telescopic optical system and the transmitter-receiver device, wherein the light beam deflecting device is controlled in accordance with a signal output from the

Abstract: A surveying instrument includes a sighting telescope having an objective lens and an eyepiece; an erecting optical system functioning so that an image formed by said objective lens is viewed as an erect image through the eyepiece; and a light shield device, positioned in an optical path extending from an incident surface of the erecting optical system to an exit surface of the erecting optical system, for preventing an off-field light bundle which is incident on the erecting optical system from reaching the eyepiece.

Abstract: An electronic distance meter includes a sighting telescope having an objective lens for sighting an object; a reflection member provided behind the objective lens, wherein the reflection member is positioned so as to be eccentric with respect to an optical axis of the objective lens; and an optical distance meter which includes a light-transmitting optical system for transmitting a measuring light via the reflection member and the objective lens, and a light-receiving optical system for receiving a portion of the measuring light which is reflected by the object, subsequently passed through the objective lens, and not obstructed by the reflection member.

Abstract: A surveying instrument includes a sighting telescope optical system, a distance measuring system which outputs first data, a phase detection autofocus system which and outputs second data, and an AF driver which moves a focusing lens of the sighting telescope optical system to bring the sighting object into focus in accordance with one of the first data and the second data. A surveying instrument is also disclosed, which includes a sighting telescope and an AF drive unit which is provided separately from the sighting telescope, wherein the AF drive unit can be mounted to and dismounted from a body of the surveying instrument.

Abstract: An electronic distance meter includes a sighting telescope having an objective lens for sighting an object; a reflection member positioned behind the objective lens; an optical distance meter which includes a light-transmitting optical system for transmitting a measuring light via the reflection member and the objective lens, and a light-receiving optical system for receiving light which is reflected by the object, subsequently passed through the objective lens and not interrupted by the reflection member; a beam-diameter varying device, provided in association with the light-transmitting optical system, for varying a beam diameter of the measuring light; and a controller which varies the beam diameter via the beam-diameter varying device in accordance with a distance from the object to the electronic distance meter.

Abstract: A surveying instrument includes a sighting telescope having an objective lens and an eyepiece; a Porro-prism erecting system; a semitransparent surface formed on a reflection surface of the Porro-prism erecting system; a beam splitting prism adhered to the semitransparent surface; and a focus detecting device which detects a focus state from a correlation between a pair of images respectively formed by two light bundles which are respectively passed through two different pupil areas of the objective lens and passed through two separate areas on the semitransparent surface. An area of a surface of the beam splitting prism which is adhered to the semitransparent surface is smaller than an effective area of the reflection surface of the Porro-prism erecting system. The semitransparent surface and the beam splitting prism are positioned so that the two light bundles are incident on the semitransparent surface at the same incident angle.

Abstract: A surveying instrument having an AF apparatus, provided with a focusing lens and a collimation telescope, includes a focus detector for detecting a focus state through the collimation telescope, and a controller for moving the focusing lens of the collimation telescope to a focal position, based on the focus state detected by the focus detector. The surveying instrument includes a single focus mode at which only one detection of the output of the focus detector and only one control operation of the controller based on the detected output are carried out, and a continuous focus mode at which a plurality of detections of the output of the focus detector and a plurality of control operations of the controller based on the detected outputs are sequentially carried out, the single focus mode and the continuous mode being selectively performed.

Abstract: An autofocus distance-measuring optical system includes a sighting telescope having an objective lens for sighting an object; an optical distance meter which includes a light-transmitting optical system for transmitting a measuring light via the, and a light-receiving optical system for receiving light reflected by the object; a focus detecting device for detecting a focus state of the sighting telescope; and a controller for controlling the sighting telescope to automatically focus on the object in accordance with the focus state detected by the focus detecting device. The focus detecting device is a phase-difference detection type which detects an in-focus state from a pair of images respectively formed by two light bundles which are passed through two different pupil areas. The two different pupil areas are positioned so as not to interfere with any optical elements of the optical distance meter.

Abstract: An optical axis correcting system includes a first afocal optical system, an optical deflector which corrects the deviation of an optical axis of light incident upon the first optical system, a second afocal optical system, and a light convergent optical system. The optical axis correcting system satisfies (1) 3.60<.vertline.fp(I)/fN(I).vertline.<5.30, (2) 1.00<.vertline.fp(II)/fN(II).vertline.<2.41, and (3) 0.12 <r1 (II)/f<0.

Abstract: In a focusing method for a surveying instrument having a sighting telescope for sighting an object and a distance measuring device for measuring the distance of the object, an automatic focusing function in which the focus state ofthe sighting telescope is detected so that an optical focusing system is automatically focused on the object in accordance with the focus state thus detected, or a distance priority focusing function in which the optical focusing system of the sighting telescope is driven in accordance with the object distance measured by the distance measuring device, is selectively used. The disclosure is also directed to a focusing apparatus and a surveying instrument.