US 7,351,944 B2Granted

Beam irradiation device

AssigneeSanyo Electric Co., Ltd.

InventorsMasato Yamada, Hitoshi Terasaki, Yoichi Tsuchiya, Shuichi Ichiura, Masahiro Higuchi, Mikio Ichihashi, Youichiro Goto, Yoshiaki Maeno

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Abstract

In a beam irradiation device of the present invention, laser beams emitted from a semiconductor laser impinge on an irradiation lens supported by a lens actuator. The laser beams that have passed through the irradiation lens change in outgoing angle in the direction of a y-z plane as the lens actuator is driven. A laser beam scan in the target region is thus performed. A part of the laser beams that have passed through the irradiation lens is reflected and separated by a beam splitter. The separated beams are converged on a PSD through a converging lens. A DSP control circuit monitors a scan position of the laser beams that have passed through the irradiation lens based on a signal from the PSD. When an irradiation position has deviated from a scan trajectory, the DSP control circuit controls an actuator driving circuit to draw the irradiation position back onto the scan trajectory. This beam irradiation device can realize a smooth and stable beam scan operation with a simple construction.

Claims10

Dependent claims

A beam irradiation device, comprising:

a beam source for emitting laser beams;
a lens for radiating the laser beams emitted from the beam source toward a target region;
displacement means for displacing the lens at least in a direction perpendicular to an optical axis of the laser beams;
scan means for driving the displacement means to cause the laser beams to perform a scan within the target region;
separation means for separating a part of the laser beams that have passed through the lens;
detection means for receiving the laser beams separated by the separation means and detecting a beam receiving position of the separated beams on a beam receiving face;
correction means for correcting a scan position of the laser beams radiated toward the target region based on the beam receiving position detected by the detection means;
and
power adjusting means for setting an outgoing power of the laser beams during a period of the scan to a first level and changing the outgoing power of the laser beams to a level different from the first level when the beam receiving position detected by the detection means has reached a position corresponding to a specific position within the target region.

6 more elements

A beam irradiation device, comprising:

a beam source for emitting laser beams;
a lens for radiating the laser beams emitted from the beam source toward a target region;
a lens actuator for displacing the lens at least in a direction perpendicular to an optical axis of the laser beams;
a scan control circuit for driving the lens actuator to cause the laser beams to perform a scan within the target region;
a spectral element for separating a part of the laser beams that have passed through the lens;
a detector for receiving the laser beams separated by the spectral element and detecting a beam receiving position of the separated beams on a beam receiving face;
a correction control circuit for correcting a scan position of the laser beams radiated toward the target region based on the beam receiving position detected by the detector;
and
a power adjusting circuit for setting an outgoing power of the laser beams during a period of the scan to a first level and changing the outgoing power of the laser beams to a level different from the first level when the beam receiving position detected by the detection means has reached a position corresponding to a specific position within the target region.

6 more elements

Dependencies are inferred from the claim text.

Facts

Application: 11/283,999Filed 22 Nov 2005
Priority: JP 2004-3489891 Dec 2004
Published: US 2006/0113462 A11 Jun 2006
Granted: 1 Apr 2008
Term ends: Not estimatedThe source records don’t support an estimate.

Classification6 codes

G01S 17/42
Systems determining position data of a target: simultaneous measurement of distance and other co-ordinates
G01S 7/4811
Constructional features, e.g. arrangements of optical elements: common to transmitter and receiver
G01S 7/4817
Constructional features, e.g. arrangements of optical elements: relating to scanning
G01S 7/491
Of systems according to group G01S17/00: details of non-pulse systems