Abstract: [Problems to be Solved] To provide a rotary encoder capable of carrying out self-calibration for a horizontal encoder as well as a vertical encoder without requiring special equipment and simply and inexpensively with a high degree of accuracy while reducing the burden on a worker.

Abstract: [Problems to be Solved] To provide a rotary encoder capable of carrying out self-calibration for a horizontal encoder as well as a vertical encoder without requiring special equipment and simply and inexpensively with a high degree of accuracy while reducing the burden on a worker.

Abstract: An electric optical distance meter is provided that makes an input power level of a reference light entering a light receiving device via an internal optical path comparable between low and high reflectivity targets.

Abstract: A surveying apparatus that is capable of automatic collimation based on an image obtained from an imaging device, which enables carrying out automatic collimation without using angle detectors, even when a telescope is rotating.

Abstract: An electric optical distance meter is provided that makes an input power level of a reference light entering a light receiving device via an internal optical path comparable between low and high reflectivity targets.

Abstract: An auto focusing mechanism is provided in a surveying instrument, such as an electronic level, that is capable of automatically focusing a telescope on a sighted staff. As a focusing lens (21b) is moved by a motor (41) along the optical axis of a telescope (20), the image of a staff (1) sighted by the telescope (20) is converted into an electrical signal by a line sensor (24). The output signal of the line sensor (24) is converted into a digital signal by an A/D converter (27) and stored in a RAM (28). Based on the data stored in the RAM (28), a microcomputer (3) monitors frequencies of the component signals, or wavelets, contained in the output signal of the line sensor (24) stored in the RAM (28). When a particular frequency of the output signal associated with the position of the focusing lens (21b) is detected a determination is made that the focusing lens (21b) is located at a focusing position, and the distance from the telescope (20) to the staff (1) is calculated.

Abstract: In a survey system in which guide light is emitted from the side of a target, and, on the side of a surveying instrument, a telescope is directed roughly toward the target by receiving the guide light so as to shorten the time required for automatic collimation, the automatic collimation of the surveying instrument can be reliably performed by removing guide light reflected by reflective objects such as windowpanes. The target has a guide light remitter that emits guide light The guide light transmitter includes a light source, a polarizing plate that changes light emitted from this light source into linearly polarized light, and a quarter-wave plate that changes this nearly polarized light into circularly polarized guide light The surveying instrument includes a direction detector and a collimation preparing means. The direction detector includes a quarter-wave plate and a polarizing plate.

Abstract: It is an object of the present invention to provide an electric optical distance wavelength meter detecting the time when the switching is completed and shortening the time required for distance measurement by immediately starting the distance measurement when measurement light and reference light are switched by a light path switching device. An electric optical distance wavelength meter includes a light emitting element for emitting measurement light toward a target placed on a measurement point; a light receiving element for receiving the measurement light coming back after reflecting on the target; a CPU for calculating the distance to the target or the object based on light receiving signals from the light receiving element; and a light path switching device for switching the measurement light so that the measurement light passes through an internal light path from the light emitting element to the light receiving element.

Abstract: A distance measuring device is provided that reduces the time required for a distance measurement without degrading accuracy of the measured value.

Abstract: [Problem] In a surveying instrument that automatically tracks or collimates a target, the target that is moved to a measurement point and is placed there can be found in the shortest possible time. [Solution Means] In a survey system made up of a target (60) and a surveying instrument (50) that automatically tracks or collimates the target, the target is provided with a direction angle sensor (86) that measures a surveying-instrument direction angle (?ta, ?tb) obtained when the target is directed toward the surveying instrument, whereas the surveying instrument is provided with a horizontal angle measuring portion that measures a target direction angle (?sa, ?sb, ?sc) indicating the direction of the target. An estimated target direction angle (?sb) is calculated from an angular difference (?o) between the surveying-instrument direction angle (?ta) and the target direction angle (?sa) obtained at the last measurement and from the surveying-instrument direction angle (?tb) obtained at the present measurement.

Abstract: A survey system is made up of a target and a surveying instrument provided with an automatic collimator that automatically collimates the target. The target includes a guide light transmitter that emits guide light, an azimuth angle sensor that detects a direction angle (?A, ?B) at which the target is directed, and a central processing unit that sends a rotation command, which includes the rotational direction of the instrument body, to the surveying instrument. The central processing unit determines the rotational direction of the instrument body based on an angular difference (?B-?A) between a direction angle (?A) obtained when the target is caused to approximately face the surveying instrument at the last measurement and a direction angle (?B) obtained when the target is caused to approximately face the surveying instrument at the present measurement.

Abstract: A surveying apparatus that is capable of automatic collimation based on an image obtained from an imaging device, which enables carrying out automatic collimation without using angle detectors, even when a telescope is rotating.

Abstract: To obtain an accurate survey value even if a centering operation is simplified without using a specific target. When a survey point S is displayed on the screen of a display 20 as an image picked up by a CCD camera 38 in a process to perform an operation for placing a surveying instrument 10 directly above the survey point S, a centering operation is ended, and the survey point S is specified as a true centering point. Accordingly, coordinates (Xs, Ys) of the survey point S in which the instrument center point 0 is defined as an origin are calculated as a decentering amount (i.e., dislocation) of the survey point S with respect to an instrument center point 0.

Abstract: A distance measuring device is provided that reduces the time required for a distance measurement without degrading accuracy of the measured value.

Abstract: [Problem] In a surveying instrument that automatically tracks or collimates a target, the target that is moved to a measurement point and is placed there can be found in the shortest possible time. [Solution Means] In a survey system made up of a target (60) and a surveying instrument (50) that automatically tracks or collimates the target, the target is provided with a direction angle sensor (86) that measures a surveying-instrument direction angle (?ta, ?tb) obtained when the target is directed toward the surveying instrument, whereas the surveying instrument is provided with a horizontal angle measuring portion that measures a target direction angle (?sa, ?sb, ?sc) indicating the direction of the target. An estimated target direction angle (?sb) is calculated from an angular difference (?o0) between the surveying-instrument direction angle (?ta) and the target direction angle (?sa) obtained at the last measurement and from the surveying-instrument direction angle (?tb) obtained at the present measurement.

Abstract: To provide means for correctly and quickly detecting the focusing lens of an auto focusing mechanism located at its focusing position. MEANS FOR CARRYING OUT THE INVENTION In the process of moving a focusing lens (21b) by a motor (41) along the optical axis of a collimating optical system (telescope (20)), the image of a staff (1) sighted by the telescope (20) is converted into an electric signal by a line sensor (24). The output signal of the line sensor (24) is further converted into a digital signal by an A/D converter (27) and stored in a RAM (28). Based on the data stored in the RAM (28), a microcomputer (3) monitors frequencies of the component signals, or wavelets, contained in the output signal of the line sensor (24) stored in the RAM (28).

Abstract: [Problem] In a surveying instrument that swiftly finds a target by emitting guide light from the target side and that has shortened the time required for automatic collimation as much as possible, the time required for automatic collimation is shortened as much as possible without increasing a burden imposed on an operator. [Solution Means] In a survey system made up of a target (60) and a surveying instrument (50) provided with an automatic collimator that automatically collimates the target, the target includes a guide light transmitter that emits guide light, an azimuth angle sensor (86) that detects a direction angle (?A, ?B) at which the target is directed, and a central processing unit that sends a rotation command, which includes the rotational direction of the instrument body, to the surveying instrument.