JPS62127813A - Optical element - Google Patents

Abstract

PURPOSE:To improve the fitting position accuracy between each optical element for constituting an optical system, by providing a positioning means on the optical element which can be formed by a mold. CONSTITUTION:Pins 2a, 2b whose optical size position accuracy has been secured are manufactured by integrating them as one body by means of mold forming on a fitting reference surface (bottom face) side of a toric lens 1, and when integrating them into a container 3, these pins 2a, 2b are fitted into long holes 4a, 4b which have been provided in advance in the container 3, and supported and fixed. In this way, the fitting position accuracy of the toric lens 1 to the container 3 is secured, and said pins can be supported and easily fixed and also with a high accuracy by a few component parts.

Description

TECHNICAL FIELD The present invention relates to an optical element that can be formed by a mold, and particularly to an optical element that can be easily and precisely fixedly supported when the optical element is incorporated into an optical device.

(2) Prior Art Conventionally, various optical elements such as lenses and prisms have been used in various optical devices, and have played the role of key components constituting the devices. In recent years, this type of optical element has been manufactured using so-called glass molds, in order to improve mass production and reduce costs.
Opportunities for molding using molds such as plastic molds are increasing. FIG. 4 shows a schematic configuration diagram of a laser beam printer (hereinafter referred to as LBP) as an example in which an optical element such as a lens formed by molding is incorporated into a device. In the figure, 8 is a container for fixing the optical system of LBP, 9
1 is a laser light source, 10 is a photoreceptor dosm, and 11 is a polygon mirror for scanning the laser light emitted from the laser light source 9 in the axial direction of the photoreceptor drum 10, which is rotated by a motor (not shown). Further, 12 is a cylindrical lens for condensing the laser light emitted from the laser light source 9 and turned into a parallel beam by a collimator lens (not shown) onto the surface of the polygon mirror 11; A spherical lens and a toric lens that conjugately converge a light beam onto the photoreceptor drum 10 and have f-θ characteristics; 15 is an LBP;
The optical system of is shown for convenience. The optical system 15 of I and BP consists of the optical elements described above, and various lenses are supported and fixed. Here, as an example, FIG. 5 shows a state in which the toric lens 14 is supported and fixed. In the figure, the same members as in FIG. 4 are designated by the same symbols. Note that 8a is an arm that positions the toric lens 14 in the optical axis direction, 8b is a pedestal that positions the toric lens 14 in a direction perpendicular to the optical axis, and 16
17 indicates a plate spring that presses the toric lens 14 toward the arm 8a, and 17 indicates a plate spring that presses the toric lens 14 toward the pedestal 8b. When the toric lens 14 is supported and fixed by each member, the leaf spring 16 on the light beam output side of the toric lens 14 is
The curved surface of the toric lens 140 is pushed, and a force is exerted on the toric lens 14 that causes slippage at the contact surface with the leaf spring 16 and tries to escape upward. Therefore, when incorporating and fixing the toric lens 14 into the optical system 15, the leaf spring 17
If the force pressing the toric lens 14 against the pedestal 8b is weak, the toric lens 14 will float above the pedestal 8b and the optical axis will be deviated. On the other hand, if the force of this leaf spring 17 is too strong, the toric lens 14 will be deformed.

Furthermore, cracks may occur at the contact portion of the toric lens 14 with the leaf spring 16.

As mentioned above, in order to accurately support and fix the toric lens 14, it is necessary to pay close attention to the amount of force applied to each support member.In particular, on an assembly line using automatic machines, cracks and the like may occur due to the amount of force applied. It was very difficult to manage. In addition to the method described above, conventional lens support and fixing methods include fitting the lens into the fitting part using the outer periphery of the lens and screwing it with a presser metal fitting, or pushing the lens against the abutting surface for positioning and using a plate. In cases where the lens is fixed with a spring, etc., or where a flat surface is provided on a part of the lens to improve mounting accuracy, the leaf spring, etc. used to fix the lens can be stopped in multiple directions. When automating assembly, it was not possible to assemble from only one direction, resulting in poor assembly efficiency and reduced productivity.

(3) Summary of the Invention In view of the above-mentioned conventional problems, an object of the present invention is to provide an optical element that can be accurately and easily fixed and supported when incorporated into an optical device.

In order to achieve the above object, the optical element according to the present invention is an optical element that can be formed by a mold, and is provided on a predetermined surface of a cough optical element or a predetermined part of a non-optical element portion integrally molded with the optical element. It is characterized in that the surface is provided with positioning means when the optical element is incorporated into an optical device.

Further objects and features of the present invention will become apparent from the following examples.

(4) Example Figures 1 and 2 show an example of the optical element according to the present invention. Figure 1 is a perspective view, and Figure 2 shows the optical axis of the optical element when it is supported and fixed. FIG. 3 is a cross-sectional view taken in three planes perpendicular to

In the figure, 1 is a toric lens molded from glass or resin, and 2a and 2b are pins provided on the mounting reference surface side of the toric lens 1, which are integrally molded. Further, 3 is a container for housing various lenses including the toric lens 1, a light source, optical elements such as mirrors, 4a,
4b is a long hole into which the pins 2a and 2b of the toric lens 1 fit, respectively; 5a and 5b are leaf springs to press the toric lens 1 so that it does not become buoyant; one end of each is fixed to the container 5. has been done.

Therefore, as shown in FIG. 1, pins 2a and 2b with guaranteed optical dimensional positional accuracy are manufactured integrally by molding between the attachment standards (bottom surface) side of the toric lens 1, and when assembled into the container 6, the pins 2a and 2b are made in advance. By fitting the pins 2a and 2b into the elongated holes 4a and 4t formed in the container 3 and supporting and fixing them, the positional accuracy of the toric lens 10 with respect to the container 3 is guaranteed. Therefore, it is possible to provide a lens that has a small number of components, can be supported and fixed simply and accurately, and is suitable for mass production.

FIG. 3 shows a modification of the optical element according to the present invention, in which 6 shows a resin molded toric lens, and 7 shows a slotted pin. A slotted pin 7 with a diameter slightly larger than the diameter of the elongated holes 4a and 4b shown in FIG.
By fitting with a and 4b, the pin y7 and the elongated hole 4a,
4b has almost no backlash and can perform positioning with even higher precision. Furthermore, it is clear that the same effect can be obtained by inserting slots in the shape of a cross.

Moreover, for the normal pins 2a, 2bK as shown in FIG. When inserted, the pressure of the leaf spring or the elastic force (pin 2a,
A method such as fixing 2b is also effective. Further, although the bottle shape shown in this embodiment is a cylinder, it is of course possible to use a conical shape, a square prism, or any other shape as long as it can be combined with an elongated hole to provide a more sufficient fit.

In addition, in the above embodiment, toric lens 1 (or 6)
A K pin is formed, but on the contrary, optical position accuracy is guaranteed at a predetermined position of the toric lens 10. It is also possible to provide a nine-long length and fit it with a pin pre-prepared on the container 3, or to insert a slot into the pin. The effect of applying division etc. is also as described above.

The present invention has been described above using a toric lens used in an optical system such as an LBP as an example, but the present invention is not limited to this toric lens, but is applicable to optical elements of any shape and use, and is applicable to high-precision positioning. , it is possible to provide an optical element that can be supported and fixed. Incidentally, if molding is possible, it is preferable because the lens is very effective in terms of productivity. For example, it would be very convenient if molding could be used to form not only two but three or more pins as described above.

In addition, in the above embodiment, pins, elongated holes, etc. are formed in predetermined positions of the toric lens, but the positioning of the pins, elongated holes, etc. can be done by molding, for example, in a non-lens member integrally molded with the outer periphery of the lens. A means for use may be provided. Furthermore, it goes without saying that the present invention can be applied not only to lenses but also to other optical elements such as prisms.

Further, in terms of structure, the most suitable optical element for the present invention is an element having a predetermined plane like the toric lens of the above embodiment, and providing positioning means such as pins and elongated holes on the plane is advantageous in molding. It is also the most effective in terms of ease and accuracy when assembling it into an actual optical device. Furthermore, it is desirable that the positioning means be of a small and simple configuration such as a pin or an elongated hole, but it may be of any size or shape as long as it does not affect the optical performance or mounting accuracy.

Furthermore, if an elastic body such as rubber is attached to the optical element or a predetermined part that comes into contact with the optical element when the optical element is assembled, or if the elastic body is used as a fixing member or a supporting member, the optical element can be prevented from being damaged. Instead, stable support and fixation can be achieved by improving adhesion.

(5) Effects of the Invention As described above, the optical element according to the present invention provides a positioning means to an optical element that can be molded by a mold, so that the attachment between each optical element constituting an optical system can be made as fast as tL. Accuracy can be improved and assembly is easy, making it very effective for automatic assembly.

Brief Description of the East Surface FIG. 1 is a perspective view showing one embodiment of the optical element according to the present invention.

! Figure s2 is a sectional view showing the optical element in Figure 1 fixed to a container.

FIG. 5 is a diagram showing a modification of the optical element according to the present invention.

FIG. 4 is a schematic configuration diagram of a laser beam printer.

FIG. 5 is a diagram illustrating a toric lens installed in a conventional manner within a laser beam precipitator.

1.6...Toric lens 2a, 2b...positioning pins 3... Container containing the optical system 4a, 4b...long 5a, 5b...plate spring 7...Positioning pin with slot 22nd 321st

Claims (4)

[Claims] (1) An optical element that can be formed by molding, which is used when incorporating the optical element into an optical device on a predetermined surface of the optical element or a predetermined surface of a non-optical element portion integrally molded with the optical element. An optical element comprising positioning means. (2) The positioning means has a convex structure, and the concave structure formed at a predetermined position of the optical device fits into the convex structure to support and fix it. The optical element described in (1). (3) The positioning means has a concave structure, and the convex structure formed at a predetermined position of the optical device is fitted into the concave structure to support and fix it. The optical element described in item 1). (4) The optical element according to claim (1), wherein the positioning means is an elastically deformable member.