Abstract

Provided are a calibration method based on dual-transmitting dual-receiving phase measurement and distance-measuring device, the calibration method comprising: step 1, forming an external optical path; step 2, forming an internal optical path; step 3, conducting a phase comparison between the second part of signals of the internal and external optical paths sequentially received by a second receiving device and the first part of signals of the internal and external optical paths sequentially received by a first receiving device, outputting two-way phase signals with part of a base reference being eliminated, conducting phase comparison again between the two-way signals with part of the base reference being eliminated, and outputting the final phase signal with the base reference being eliminated. The distance-measuring device comprises a transmitting device (1, 301, 403, 502), a first reflective surface (2, 302, 402, 503), a first receiving device (3, 506), a first filter (4, 304, 405, 504), a second filter (5, 305, 406, 505), a second receiving device (8, 507), and a phase detector (307, 411, 509). The calibration method and distance-measuring device realizes phase compensation and calibration, avoids introducing uncertain phase noise into a circuit due to environmental changes, improves distance-measurement precision, and reduces system costs.

IPC Classes  ?

• G01S 17/36 - Systems determining position data of a target for measuring distance only using transmission of continuous waves, whether amplitude-, frequency-, or phase-modulated, or unmodulated with phase comparison between the received signal and the contemporaneously transmitted signal
• G01S 7/497 - Means for monitoring or calibrating
• G01C 3/00 - Measuring distances in line of sightOptical rangefinders

Abstract

A calibration method and a distance measurement device thereof based on phase measurement of a double-wavelength laser tube. The method comprises the following steps: step 1, a first wavelength light-wave is transmitted to a target to be measured through a first light filter from a light wave transmitting device during forming an external light path, the light-wave reflected by the target is received by a receiving device, as an external light path signal, the first wavelength light-wave is modulated from a high frequency oscillating signal (S101); step 2, a second wavelength light-wave is transmitted to the receiving device through a second light filter from the light wave transmitting device during forming an internal light path, as an internal light path signal of a basic reference, the second light-wave is generated from the high frequency oscillating signal (S102); step 3, the receiving device compares phases of the two sequentially received light-waves, and outputs a phase signal eliminated the base reference (S103).

IPC Classes  ?

• G01S 17/36 - Systems determining position data of a target for measuring distance only using transmission of continuous waves, whether amplitude-, frequency-, or phase-modulated, or unmodulated with phase comparison between the received signal and the contemporaneously transmitted signal
• G01C 3/00 - Measuring distances in line of sightOptical rangefinders
• H01S 5/00 - Semiconductor lasers

Abstract

An optical system structure of a laser range finder, comprising a laser emission light source (1), a collimating objective lens (2) disposed in front of the laser emission light source (1), an optical receiver (5) and a receiving objective lens converging the reflected light to the optical receiver (5); the receiving objective lens is a free-form surface optical element (14) consisting of an aspheric part and a toroidal part; an infinitely far reflected light passes through the aspheric part of the receiving objective lens and focuses on the optical receiver (5); and a short distance reflected light passes through the toroidal part of the receiving objective lens and covers the surface of the optical receiver (5). The optical system structure satisfies short distance and long distance high precision measurements, has a simple structure, good measurement stability and is more cost-effective than conventional measurement devices, and facilitates miniaturization.

IPC Classes  ?

• G01S 7/481 - Constructional features, e.g. arrangements of optical elements
• G01S 7/48 - Details of systems according to groups , , of systems according to group
• G01S 17/08 - Systems determining position data of a target for measuring distance only
• G01C 3/00 - Measuring distances in line of sightOptical rangefinders

Abstract

An optical system structure of a laser range finder, including a laser emitting light source (1), a collimation objective (2) located in front of the laser emitting light source (1), an optical receiver (5) and a receiving objective (14) converging the reflected light rays to the optical receiver (5). The receiving objective (14) is a free-form surface optical element, formed by an aspheric surface part (16) and a toroid part (15). Those reflected light rays at infinity pass through the aspheric surface part (16) of the receiving objective (14) to focus on the optical receiver (5); and those close-range reflected light rays pass through the toroid part (15) of the receiving objective (14) to cover a light receiving area (6) of the optical receiver (5). The optical system structure of the laser range finder can meet measurements for long distance and close range, with a simple structure and good measurement stability, advantageous in achieving miniaturization.

IPC Classes  ?

• G01S 7/481 - Constructional features, e.g. arrangements of optical elements
• G01S 7/08 - Cathode-ray tube displays with vernier indication of distance, e.g. using two cathode-ray tubes

Abstract

Phase measurement calibrating method, calibrating device and ranging device based on the liquid crystal light valve principle are disclosed. A light wave is emitted by a system light wave emitting device (1) to a tested target through a first liquid crystal light valve (3). The light wave is reflected and returned from the tested target to be focused by an optical device, and is received by a receiving device (7). The received light wave is used as the external light path light wave of the system measurement. While the light wave is passing through the first liquid crystal light valve (3), a part of the light wave is reflected by the first light valve (3) to pass through a second liquid crystal light valve (4). The light wave passing through the second liquid crystal light valve (4) is received directly by the receiving device (7) and used as the internal light path light wave for fundamental reference of the system phase measurement. The first liquid crystal light valve (3) and the second liquid crystal light valve (4) are switched orderly while the system operates so that the receiving device (7) is utilized for comparing phases of the internal optical path light wave and the external optical path light wave received orderly to output a signal for eliminating a fundamental reference. The calibrating method achieves phase compensation and calibration, increases measurement accuracy of a laser ranging operation, and enhances ranging stability of the system.

IPC Classes  ?

• G01S 7/497 - Means for monitoring or calibrating
• G01S 17/36 - Systems determining position data of a target for measuring distance only using transmission of continuous waves, whether amplitude-, frequency-, or phase-modulated, or unmodulated with phase comparison between the received signal and the contemporaneously transmitted signal