BRIEF DESCRIPTION OF THE FIGURES
The accomplishment of this and other objects of the invention will become apparent from the following descriptions and its accompanying figures of which:
FIG. 1 is an exploded perspective view of a conventional laser module;
FIG. 2 is a cutaway view of the conventional laser module after assembly;
FIG. 3 is an exploded perspective view of the invention;
FIG. 4 is a cutaway view of the invention; and
FIG. 5 is a cutaway view of the invention after assembly.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
First of all, referring to FIGS. 2 and 3, the invention is installed at front end of a laser diode 10 of a drive circuit board 20. The invention includes a transparent sleeve 70 that is integrally injection molded from plastic material. An aspheric lens 71 is formed at the top of the transparent sleeve 70. The inner wall of the transparent sleeve 70 is provided with a focus adjusting slope 72 facing the laser diode 10. The focus adjusting slope 72 is outwardly inclined and has an angle (θ) with respect to the horizontal plane. As shown in FIG. 5, the conventional optical unit is so changed that it is injection molded out of transparent plastic material, thereby reducing the quantity of required components. Accordingly, the simplification of the components is ensured, thereby reducing the material and assembly cost. Moreover, the exterior allows a more complicated variation according to different requirements. Due to the transparency of the material, the examiner can learn from the outside if the laser diode lights up. In this way, the risk of direct observation can be avoided. Meanwhile, the lighting status can be observed from the outside.
What is more important, the focus adjustment of the invention is very convenient and precise. As shown in FIG. 5, when the laser diode 10 and the drive circuit board 20 are inserted along the focus adjusting slope 72 into the transparent sleeve 70, the adjustment can be done by an axial displacement on the focus adjusting slope 72 such that an optimal focus between a projecting beam 80 and the aspheric lens 71 is created. Thereafter, the laser diode 10 is fixed by glue 73. Unlike the conventional turning way, the focus adjustment in accordance with the invention can avoid undesirable arched displacement. Besides, the transparent sleeve 70 is so transparent that an easy observation is guaranteed during the adjustment process. Therefore, the invention permits a convenient adjustment and a high accuracy.
Many changes and modifications in the above-described embodiments of the invention can, of course, be carried out without departing from the scope thereof. Accordingly, to promote the progress in science and the useful arts, the invention is disclosed and is intended to be limited only by the scope of the appended claims.
Patent Application
20070247728
