Laser transmitter with thermally induced error compensation and method of transmitter compensation
AssigneeTrimble Navigation Limited
InventorJ. Greco
Life of this patent
Estimating the term…
Abstract
The transmitter for projecting a beam of laser light includes a source of a beam of laser light, and a projection arrangement for directing the beam of laser light at a selected grade. The transmitter further includes a temperature sensor for detecting the temperature of said transmitter, and a temperature correction circuit, including a look-up table, responsive to said temperature sensor, for adjusting said projection arrangement in dependence upon offset grade values that are stored in said look-up table for a plurality of transmitter temperatures. These offset grade values are separately determined on an empirical basis for each transmitter, such that temperatures induced errors in the direction of the beam of laser light are compensated.
Claims13
A transmitter for projecting a beam of laser light, comprising:
- a source of laser light;
- a projection arrangement for directing the laser light from said transmitter, said projection arrangement including a level vial;
- a temperature sensor circuit for detecting error induced by a temperature change in said level vial where said error is a function of vial temperature of said level vial itself;
- and
- a temperature correction circuit, responsive to said temperature sensor circuit, that adjusts said projection arrangement to compensate the direction of the laser light as a result of said error detected by said temperature sensor circuit.
A transmitter for projecting a beam of laser light, comprising:
- a source of laser light;
- a projection arrangement for directing the laser light from said transmitter, said projection arrangement including a level vial having a quantity of fluid therein;.
- a temperature sensor circuit for detecting the resistance of said quantity of fluid in said level vial, said resistance being relied to the temperature of said level vial, and
- a temperature correction circuit, responsive to said temperature sensor circuit, for adjusting said projection arrangement to compensate for errors in the direction of the laser light as a result of temperature induced variation in said level vial.
Dependencies are inferred from the claim text.