JPH0588061A - Light source device - Google Patents

Abstract

PURPOSE:To stick a collimator lens to a holding member directly or through a lens holder by giving sufficient sticking strength and to simultaneously reduce the decentering of the lens. CONSTITUTION:A collimator lens 14 is movably inserted in the engagement hole 13a of a flange 13 being the holding member through a lens holder 15 and the position thereof is adjusted. Thereafter, when adhesive agent is poured from a notch 21 to a part obtained by forming the inside diameter D1 of the entrance part of the hole 13a little bit larger than the inside diameter D2 of the other part, it permeates in a circumferential direction at the part of the inside diameter D1 of the holes 13a without staying near the notch 21 and circulates on the inside diameter D2 side. Thus, the bias of the circumferential direction of the adhesive agent is eliminated and the sticking strength is raised. Besides, the decentering of the lens 14 is also eliminated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light source device using a semiconductor laser used in a laser printer or the like.

[0002]

2. Description of the Related Art As a conventional light source device using a semiconductor laser, for example, as shown in FIG. 4, a semiconductor laser 1 is attached to a base 2 and is fitted to a flange 3 serving as a holding member fixed to the base 2. The lens holder 5 holding the collimator lens 4 in the fitting hole 3a is shown by the arrow A in the optical axis direction.
In such a manner that the semiconductor laser 1 can be adjusted so that the lens holder 5 is located at the focal position of the collimator lens 4.
The light sources of No. 3 and No. 3 are adjusted and positioned so as to match, and in that state, as shown in FIG. There is one in which the lens holder 5 is fixed to the flange 3.

Then, the lens holder 5 is covered with a cap-shaped aperture forming member 6 having an aperture 6a as shown in FIG. 6b is fitted into a positioning groove 3c formed in the flange 3 with a phase different from that of the notch 3b by 180 °, whereby the positioning is fixed.

[0004]

However, such a conventional light source device has a notch 3b as shown in FIG.
When the adhesive Ad is flowed into the fitting hole 3a, it usually penetrates deep into the fitting hole 3a due to a capillary phenomenon, but generally, the inner diameter of the fitting hole 3a of the flange 3 and the lens holder 5 to be fitted therein. The clearance of the outer diameter is about 0.01 to 0.03 mm, which is as small as possible in order to prevent the decentering of the collimator lens 4. Therefore, as shown in the figure, the adhesive Ad has a notch 3
Since it hardens in a state where it has permeated only around b (indicated by hatching the permeated portion of the adhesive in FIG. 5), it often does not reach the entire circumference of the fitting hole 3a. There is a problem that the adhesive strength may not be obtained.

Further, when the adhesive hardens in the biased position, the lens holder 5 may be eccentric due to the strain due to the stress. Furthermore, when the viscosity of the adhesive is high, it hardly penetrates between the lens holder 5 and the fitting hole 3a of the flange 3, so most of the adhesive accumulates in the notch 3b and hardens. Since it blocks the notch portion, even if the notch 3b is used as a positioning groove for positioning the aperture forming member 6, this cannot be done. Therefore, conventionally, the adhesive inflow notch 3b for fixing the lens holder 5 to the flange 3 and the positioning groove 3c for mounting and positioning the aperture 6 have been separated.

The present invention has been made in view of the above problems, and a collimator lens can be bonded directly or via a lens holder to a holding member such as a flange with sufficient bonding strength. An object of the present invention is to provide a light source device in which the collimator lens has less eccentricity with respect to the holding member. It is also an object of the present invention to enable positioning of a member having an aperture at a predetermined position of the holding member without providing a dedicated notch for positioning the member.

[0007]

In order to achieve the above object, the present invention provides a light source device as described above, wherein a fitting hole is formed in a holding member for holding a collimator lens directly or via a lens holder. , The collimator lens is movably fitted in the fitting hole directly or via a lens holder so as to be fixed by an adhesive, and the inner diameter of the entrance portion of the fitting hole is slightly smaller than the inner diameters of other portions. It is formed to be large in size, and a notch is formed at the entrance to allow the adhesive to flow in.

In the light source device, a projection is formed on a member having an aperture for shaping a parallel light beam emitted from a semiconductor laser and passed through a collimator lens, and the projection is fitted into a notch of a holding member. The member having the aperture may be positioned.

[0009]

According to the light source device configured as described above, the collimator lens is movably fitted into the fitting hole of the holding member directly or through the lens holder, and after adjusting the position, the entrance portion of the fitting hole is adjusted. If the adhesive flows into the notch formed in the, the inner diameter of the fitting hole at the inlet is slightly larger than the inner diameters of the other parts, so the adhesive accumulates near the notch. The inner diameter of the fitting hole, which is slightly increased, penetrates in the circumferential direction. Therefore, since the bias of the adhesive is eliminated, sufficient adhesive strength can be obtained and the decentering of the collimator lens is eliminated.

Further, in the light source device, a projection is formed on a member having an aperture for shaping a parallel light beam emitted from a semiconductor laser and passing through a collimator lens,
If the protrusion is fitted into the notch of the holding member to position the above member, the adhesive that has flowed into the notch at the inlet of the fitting hole does not accumulate there and the circumferential direction of the fitting hole Since the adhesive does not harden and block the cutout portion as it penetrates into the substrate, the protrusion of the member having the aperture can be fitted and positioned there.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be specifically described below with reference to the drawings. FIG. 1 is a cross-sectional view showing the structure of a light source device according to the present invention, and FIG. 2 is an exploded perspective view similarly showing the parts constituting the light source device in an exploded manner. This light source device holds a semiconductor laser 11 that emits a laser beam, a collimator lens 14 that makes the laser beam a substantially parallel light flux, and the collimator lens 14 via a lens holder 15 (directly holds the collimator lens. The flange 13 serving as a holding member may be provided.

The semiconductor laser 11 is a laser diode, and is fixed by being press-fitted into a stepped hole 12a formed in the center of the base 12 as shown in FIG.
The printed circuit board 17 is integrated with the base 12
The guide pins 12c, 12c formed at the tips of the book spacers 12b, 12b are fitted into the respective positioning holes 17a formed correspondingly, and heat or the like is applied to the tip portions thereof to make them phantom lines in FIG. It is melted and fixed as shown in.

The base 12 is attached to the printed circuit board 1
Each lead wire 1 of the semiconductor laser 11 in the state of being fixed to 7
1a is attached to the lead wire 11 at the substantially center of the printed circuit board 17.
The holes 18 corresponding to the number of a are fitted into the holes 18, respectively, and they are joined to the conductive pattern portions on the printed board 17 by soldering.

A flange 13 is fixed to the surface of the base 12 on the left side in FIG. 1 by two screws 19 and 19 (see also FIG. 2), and the substantially center of the flange 13 is the semiconductor laser 1.
1, and the fitting hole 13a is formed there by projecting to the opposite side,
The collimator lens 14 is movably fitted into the fitting hole 13a through the lens holder 15 so as to be fixed with an adhesive, and the inner diameter D1 of the inlet portion 13b of the fitting hole 13a is changed to the inner diameter of the other portion. It is formed to be slightly larger than D2 by, for example, about 0.1 mm, and a notch 21 for allowing the adhesive to flow is formed in the inlet portion 13b thereof.

The lens holder 15 having the collimator lens 14 fixed therein has an outer diameter such that the clearance with the inner diameter D2 of the fitting hole 13a is, for example, 0.01 to 0.03 mm, and the collimator lens is as much as possible. The eccentricity of 14 is kept small. The fitting hole 13a has an inner diameter D1 only at the portion having the notch 21 as shown in FIG.

Then, the lens holder 15 to which the collimator lens 14 is fixed is attached to the fitting hole 13a of the flange 13.
1 is inserted into a predetermined position as shown in FIG. 1 and is adjusted so that the light source of the semiconductor laser 11 coincides with the focal position of the collimator lens 14, and the flow from the notch 21 formed in the flange 13 Inject a good adhesive.

Before fixing the lens holder 15, the light emitting point of the semiconductor laser 11 is changed to the collimator lens 14.
The two screws 19 are loosened in advance so as to be aligned with the optical axis of, and the position of the flange 13 is adjusted, and the screw 19 is tightened at that position to fix the flange 13 to the base 12.

The adhesive introduced from the notch 21 is
First, the inner diameter D1 of the large-diameter inlet portion 13b is used as a flow path to permeate the entire circumference, and thereafter the inner diameter D1 is gradually increased.
As shown in FIG. 3, it enters into the inner side of the inner diameter D2 having a diameter slightly smaller than that (adhesive Ad). Therefore, substantially the entire circumference of the lens holder 15 can be bonded to the flange 13 uniformly. Therefore, since the bias of the adhesive is eliminated, sufficient adhesive strength can be obtained and the decentering of the collimator lens 14 is eliminated.

The lens holder 15 has a cap shape as shown in FIG. 2, and an aperture forming member 22 is formed with an aperture 22a for shaping a parallel light beam emitted from the semiconductor laser 11 and passing through the collimator lens 14. Is inserted with reference to the outer peripheral portion of the lens holder 15 (see FIG. 1). In the aperture forming member 22, a protrusion 22b is formed at one end of the edge corresponding to the notch 21 of the flange 13, and the protrusion 22b is fitted into the notch 21 to position and fix the aperture forming member 22. There is.

At this time, if the hardened adhesive is accumulated in the notch 21, the protrusion 22b cannot be fitted to a predetermined position in the notch 21 (position shown by phantom line in FIG. 1). However, according to this embodiment, as described above, the adhesive that has flowed in from the notch 21 permeates the entire circumference of the fitting hole 13a using the portion having the inner diameter D1 of the inlet portion 13b as a flow path. Since no adhesive remains on the cutout 21, the projection 22b can be fitted to a predetermined position of the cutout 21 to reliably position and fix the aperture forming member 22.

Thus, the notch 2 through which the adhesive flows in
Since 1 is also used for positioning and fixing the aperture forming member 22, there is no need to provide a notch dedicated to positioning the aperture, so that the processing steps can be saved accordingly.

[0022]

As described above, according to the present invention, when the adhesive flows in from the notch formed at the inlet of the fitting hole of the holding member, it penetrates the entire circumference of the fitting hole. Therefore, the collimator lens can be adhered to the holding member substantially uniformly over the entire circumference directly or via the lens holder, so that sufficient adhesive strength can be obtained and the deviation of the adhesive can be prevented. As a result, eccentricity of the lens holder due to stress strain due to environmental changes and hardening of the adhesive can be alleviated.

If the projection provided on the member having the aperture is fitted into the notch of the holding member to position the member, the adhesive having a slightly larger inner diameter is provided at the entrance of the fitting hole. Since the flow path is secured, the adhesive will penetrate into the cutout without remaining, so it is possible to securely fit the protrusion to the predetermined position of the cutout and position and fix it. Therefore, it is not necessary to provide a dedicated notch for positioning the member having the aperture, so that the processing step can be omitted.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a light source device according to the present invention.

FIG. 2 is an exploded perspective view similarly showing the components of the light source device in an exploded manner.

FIG. 3 is an explanatory diagram showing a state in which the adhesive that has flowed in from the notch 21 formed in the flange 13 of FIG. 1 permeates into the inner side of the fitting hole and wraps around the entire circumference.

FIG. 4 is a schematic view showing a simplified configuration of a conventional light source device.

5 is an explanatory diagram showing a state in which when the adhesive is poured from the notch formed in the flange in the light source device of FIG. 4, the adhesive is solidified around the notch.

[Explanation of symbols]

11 Semiconductor Laser 12 Base 13 Flange (Holding Member) 13a Fitting Hole 14 Collimator Lens 13b Inlet 15 Lens Holder 21 Notch 22 Aperture Forming Member 22a Aperture 22b Protrusion

Claims (2)

[Claims] 1. A semiconductor laser for irradiating a laser beam, and a collimator lens for converting the laser beam into a substantially parallel luminous flux,
In a light source device provided with a holding member that holds the collimator lens directly or via a lens holder, a fitting hole is formed in the holding member, and the collimator lens is provided in the fitting hole directly or via the lens holder. A notch for allowing the adhesive to flow into the inlet so that the inlet of the fitting hole is slightly larger than the inner diameter of the other portion so that it can be movably fitted and fixed with an adhesive. A light source device comprising: 2. The light source device according to claim 1, wherein a projection is formed on a member having an aperture for shaping a parallel light beam emitted from the semiconductor laser and passed through the collimator lens, and the projection is formed on the holding member. The light source device is characterized in that the member is positioned by being fitted into the notch.