Patent ID: 9612514
Date: 2017-04-04
CPC Classifications: F21V,G02B,G03B,H04N

Claim:
1. A light emitting device, comprising: at least one light source unit, which includes a laser unit and a collimating lens corresponding to the laser unit, wherein a light emitting surface of the laser unit is a rectangle, wherein a divergence angle of a laser light emitted by the laser unit in a cross-section that goes through a long side of the rectangle is less than a divergence angle of the laser light in a cross-section that goes through a short side of the rectangle; and a focusing lens, wherein the collimating lens converges the laser light emitted by the laser unit and directs it onto the focusing lens, and the focusing lens focuses the laser light from the collimating lens onto a target plane to form a predetermined light spot, wherein the laser unit is located on an optical axis of the collimating lens at a position away from a focal point of the collimating lens, wherein the predetermined light spot has a predetermined aspect ratio, and wherein a distance between the laser unit and the focal point of the collimating lens is determined based on the predetermined aspect ratio.