JPH0433792A - Optical equipment for laser marking - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an optical device for laser marking, and in particular,
The present invention relates to an optical device for laser marking using a mask.

[Conventional technology]

As described in Japanese Utility Model Application Publication No. 63-196382 (FIG. 5), the conventional device shapes the beam emitted from the laser light source 10 using a beam shaping lens 20, and masks it as non-collimated light 111. A beam 112 transmitted through the mask is focused by a lens 22, and the image of the mask is irradiated onto a package 30 such as an IC1 electronic component. The optical system uses a non-collimating system, so that the reflected light from the mask returns to the beam shaping lens, where the beam is converged and prevents the reflected spot with high power density from damaging the optical elements and gimbals.

[Problem to be solved by the invention]

The above-mentioned conventional technology does not take into consideration the simplification of optical design and uses a non-collimated optical system, which makes optical design difficult for determining the position and focal length of the optical element to be used.

An object of the present invention is to simplify optical system design.

[Means to solve the problem]

In order to achieve the above object, the present invention uses a collimating optical system that is easy to optically design, and arranges the mask so that the angle between the incident direction of the laser beam and the tangential direction of the mask reflection surface is not 90 degrees, or , the mask has a reflective surface shape.

[Effect]

By attaching the mask that reflects unnecessary light at an angle with respect to the laser beam light, the light reflected by the mask does not converge near the light source, and the laser light source is not damaged.

By making the mask shape concave, the reflected light from the mask is converged inside the focal length of the lens of the beam shaping means,
Since the diverging light returns to the laser light source, no damage is caused to the laser light source.

By making the mask shape convex, the reflected light from the mask diverges to the outside of the lens of the beam shaping means, and the diverging light returns to the laser light source, thereby preventing damage to the laser light source.

By making the mask shape uneven, the light reflected by the mask becomes diffusely reflected light, and the diverging light returns to the laser light source, so that no damage is caused to the laser light source.

〔Example〕

Embodiments of the present invention will be described below with reference to FIG.

FIG. 1 shows a laser marking optical system according to an embodiment of the present invention, in which a laser light source 10 guided by an optical fiber passes through a beam shaping means and irradiates a mask 21. mask 21
The transmitted beam 212 passes through the imaging lens 22 and becomes a beam 213 to print a pattern on the mask onto the workpiece 3o. At this time, since the mask 21 is tilted, the reflected light does not form an image on the gimbal 41 or the surface of the laser light source 10 or its vicinity, and does not cause damage.

FIG. 2 shows a second embodiment of the invention. By making the mask shape concave, the beam reflected on the mask is converged inside the focal length of the lens of the beam shaping means,
Since the divergent light returns to the laser light source, there is no damage to the laser light source.

FIG. 3 shows a third embodiment of the invention. By making the mask reflection surface a convex surface, the beam reflected on the mask diverges to the outside of the beam shaping means, and the divergent light returns to the laser light source, so that the laser light source is not damaged.

FIG. 4 shows a fourth embodiment of the invention. By making the mask reflection surface uneven, the beam reflected on the mask becomes diffusely reflected light and divergent light returns to the laser light source.
There is no damage to the laser light source.

〔Effect of the invention〕

According to the present invention, in addition to using a collimating optical system that facilitates optical design, the arrangement position of the mask, the mask The simple method of shaping can eliminate damage to the laser oscillator due to light reflected by the mask, making it easier to design the optical system.

[Brief explanation of drawings]

1 to 4 are detailed explanatory views of different embodiments of the present invention, and FIG. 5 is a side view of a conventional laser marking optical system configuration. 10...Laser light source, 40.41...Gimbal, 2
0... Lens of beam shaping means, 21... Mask,
22... Imaging lens, 30... Workpiece, 110
．． 111゜112.113,120,121,210,
211゜Figure 1 Figure 3 Figure 4

Claims (1)

[Claims] 1. For laser marking, in which a beam emitted from a laser light source is expanded by a beam shaping means to match the shape of the mask, and a pattern formed on a mask that reflects unnecessary light is imaged with a lens. In the optical system, the reflective surface of the mask is not perpendicular to the laser light source so that the beam reflected by the mask does not converge near the laser light source after returning to the beam shaping means. An optical device for laser marking, characterized in that it is installed in the following manner. 2. The optical device for laser marking according to claim 1, wherein the reflective surface of the mask is a concave surface. 3. The optical device for laser marking according to claim 1, wherein the reflective surface of the mask is a convex surface.