JPH0749454Y2 - Holding device for semiconductor laser package - Google Patents

Description

[Detailed description of the device]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a semiconductor laser package holding device for improving the image quality of a laser printer.

[Prior art]

In an optical system of a laser printer which holds a semiconductor laser package as shown in FIG. 3 in a collimator unit 3 as shown in FIG. 4 and scans an information signal image as a light source of the laser printer, a surface of a photoconductor or a surface of a recording medium is used. It is known that when the minor axis direction of the elliptical cross section of the laser beam is oriented in the scanning direction on the surface to be scanned, the beam dots become uniform and a good image is obtained. Therefore, since the groove 2 provided on the flange cylindrical surface 9 of the semiconductor laser package 1 serves as an index indicating the direction of the elliptical cross section, this is set as a predetermined direction determined by the mounting position of the collimator unit to the optical system. The flange surface 4 of the semiconductor laser package is abutted against the stepped surface 4 ′ of the collimator unit, the nut 5 is screwed in, and the rear surface 6 of the flange of the semiconductor laser package is fitted together. It is fixed by pressing. If the groove 2 of the semiconductor laser package 1 as described above is used as an index, the position of the index may move when tightening with the nut 5, so a set screw is raised from the collimator unit to the groove and fixed. It is also possible to do it.

[Problems to be solved by the device]

In the prior art, using the groove 2 of the semiconductor laser package as an index as described above is unstable in setting. Therefore, as another method, if set screws are set in the collimator unit 3 in the groove,
The width of the groove is 1 mm, the depth is 0.4 mm, the length is about 1.5 mm, the thickness of the collimator unit is large, the screwing work is difficult, and the workability is poor. SUMMARY OF THE INVENTION It is an object of the present invention to solve the above problems and provide a semiconductor laser package holding device that can be set accurately and can be easily assembled and disassembled.

[Means for solving problems]

The object of the present invention is to provide a semiconductor laser package holding device for holding a semiconductor laser package on a lens barrel of a lens unit, wherein the semiconductor laser package is provided on the stepped surface of the lens barrel in the lens barrel having a stepped surface inside. The flange of the semiconductor laser package is fitted so that the flange surface of the semiconductor laser package is fitted, and the locking member provided with the protrusion is pressed from the rear surface of the flange of the semiconductor laser package, and the protrusion is the semiconductor laser package. This is achieved by a holding device for a semiconductor laser package, which is fixed to the lens barrel so as to be fitted in a groove provided in a flange cylindrical surface.

【Example】

An embodiment of the present invention is shown in FIGS. 1 (a) (b) (c) and 2
This will be described with reference to the figure. FIG. 2 is a schematic view of an optical system in which a semiconductor laser package holding device of the present invention is incorporated. The semiconductor laser package 1 is held by a collimator unit 13 in which a collimator lens 11 is incorporated and is used as a light source of a laser printer. Cylindrical lens 21 and reflector 2 for signal image
2, a polygon (polyhedral mirror) 23, an fθ lens 24, a cylindrical lens 25, and a reflecting mirror 26, and a scanning image is formed on the photoconductor 27. Here, the arrow A is the scanning direction of the beam, and if this direction and the minor axis direction of the elliptical cross section of the laser beam are made to coincide with each other, a uniform beam dot can be obtained and a high quality image can be obtained. It is necessary to securely hold the semiconductor laser package in a predetermined direction.
1 (a) (b) (c) shows an embodiment of the holding device of the present invention. The collimator unit 13 receives the laser semiconductor package 1 with its flange surface 4 on the stepped surface 14 ',
The outer lens barrel portion whose cylindrical surface 9 is fitted with the inner diameter surface 19 '.
13a and the lens barrel 13b holding the collimator lens 11, the optical axes of both lens barrels are aligned and the position is adjusted to a predetermined length in the optical axis direction, and at that position the set screw It is fixed at 18 mag. The semiconductor laser package 1 has a rear surface 6 of the flange.
Is held by a locking member 17, and a protrusion 17a formed by notching at one position of the locking member is hooked in the groove 2 of the flange portion of the semiconductor laser package 1 and the locking member is
17 is firmly fixed to the rear end surface 20 of the outer lens barrel portion 13a with screws 29. The package 1 is the outer lens barrel portion.
It has a complete detent against 13a. The outer lens barrel portion 13a is attached and fixed to a predetermined position of the optical system as shown in FIG. With such a semiconductor laser package holding device, the minor axis direction of the elliptical cross section of the laser beam is reliably and easily held so as to coincide with the scanning direction A. In order to do so, it is preferable that the semiconductor laser is mounted in a direction such that the PN junction surface is orthogonal to the scanning direction. It should be noted that the locking member 17 has a U-shaped opening 17b, which is locked without disconnecting or disconnecting the connection cord 30 for inserting the information signal image from the modulation circuit board to be inserted into the semiconductor laser package 1. Since the members can be removed, it is convenient for disassembly and assembly adjustment.

[Effect of device]

The present invention makes it possible to hold a semiconductor laser package with a simple and reliable device, maintain a good image quality of a laser printer, facilitate the processing and assembly of the device, and reduce the manufacturing cost.

[Brief description of drawings]

FIG. 1 (a) is a top view of an embodiment of the present invention, FIG. 1 (b) is a side view of a combination of the locking member and a semiconductor laser package, and FIG. 1 (c) is the holding of the present invention. FIG. 2 is a side sectional view of a collimator unit incorporating the apparatus, FIG. 2 is a schematic view of an optical system of a laser printer incorporating the present invention, FIG. 3 is a perspective view of a semiconductor laser package, and FIG.
The figure is a sectional view of a collimator unit having a conventional holding device. 1 ... Semiconductor laser package 2 ... Groove 3 ... Collimator unit 3a ... Outer lens barrel portion, 3b ... Lens barrel portion 4 ... Flange surface 4'14 '... Stepped surface 5 ... Nut 6 ... Flange rear surface 9 ... Flange cylindrical surface, 9 ', 19' ... Inner diameter of outer lens barrel 11 ... Collimator lens 13 ... Collimator unit 13a ... Outer lens barrel portion 13b ... Lens barrel portion 17 ... Locking member 17a ... Protrusion, 17b ... Opening portion 18 ... Set screw 20 ... Rear end face of outer lens barrel 29 ... Stop screw 30 ... Connection cord

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) Bibliographic references Sho 59-33130 (JP, U)

Claims (1)

[Scope of utility model registration request] 1. A semiconductor laser package holding device for holding a semiconductor laser package on a lens barrel of a lens unit, wherein the semiconductor laser is provided on the stepped surface of the lens barrel in the lens barrel having a stepped surface inside. The flange of the semiconductor laser package is fitted so that the flange surface of the package is attached, and the locking member provided with the protrusion is pressed from the rear surface of the flange of the semiconductor laser package and the protrusion is the semiconductor laser package. A holding device for a semiconductor laser package, characterized in that the holding device is fixed to the lens barrel so as to be fitted in a groove provided on the flange cylindrical surface.