JPH04137376U - optical writing head - Google Patents

Abstract

(57) [Summary] [Purpose] To provide good contact with a belt-shaped member to be written and to increase productivity. [Structure] The contact portion of the substrate 11 with the member 12 to be written is formed in a convex curved shape at a position biased toward one end of the substrate 11, thereby achieving good contact with the member 12 to be written. and can print with good quality.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

The present invention is based on a belt-shaped member to be written, such as a photoreceptor, which runs in a fixed direction. LED array head of an electrophotographic recording device used in contact with a surface Regarding optical writing heads such as

0002

[Description of prior art]

In recent years, exposure devices for optical writing have been used in electrophotographic recording devices such as page printers. An LED array head is used as an LED array head, and this LED array head is A device that is placed in contact with the surface has been developed.

0003 For example, as shown in FIG. Almost in the center of the array plate (FAP) 1a, there are An optical fiber bundle 1b is buried therein, and a diagram of this optical fiber bundle 1b is shown below. The LED chip 1c is placed on the substrate 1a so as to face the light incident side which is the lower side. It is located in This LED chip 1c is driven through a wiring conductor pattern 1d. It is connected to the dynamic driver IC circuit 1e. Then, the emission of this LED chip 1c The light emitted from the light section 1f passes through the optical fiber bundle 1b to the belt-shaped photoreceptor 2. An image is formed and image information is written.

0004 At this time, the substrate 1a of the LED array head is a relatively large block. It is generally used by slicing and cutting a square member into a flat or convex shape. ing. This sliced and carved material is then polished and finished on both sides. It will be done.

[0005]

[Problem that the idea aims to solve]

However, with the conventional head structure described above, it takes time and effort to process the substrate 1a. This poses a problem in productivity, and also in contact with the photoreceptor 2 side. In particular, in the case where the substrate 1a is carved into a convex shape, There is a problem in that the cost is high because the number of pieces to be produced is limited.

[0006] Therefore, the present invention has been proposed for writing on a belt-shaped member to be written such as a belt-shaped photoreceptor. The objective is to provide an optical writing head with good contact properties and high productivity. Ru.

[0007]

[Means to solve the problem]

In order to achieve the above-mentioned object, the optical writing head according to claim 1 of the present invention has a belt-like shape. a substrate placed in contact with the member to be written; and a contact of the substrate to the member to be written; The contact portion includes an optical fiber bundle embedded in an aligned state so as to constitute a light guiding portion. In the optical writing head, the contact portion of the substrate with the member to be written is connected to one part of the substrate. It is characterized by being formed in a convex curved shape at a position biased towards the end side. .

[0008] Further, the optical writing head according to a second aspect of the present invention is the optical writing head according to the first aspect, The upstream side in the traveling direction of the member to be written at the contact part with the member is the surface of the member to be written. The feature is that the substrate is arranged at an angle so that it forms a small angle below a certain value with respect to the surface. It is said that

[0009] Furthermore, in the optical writing head according to claim 3, in claim 2, the angle is set to 3 to 15. It is characterized by a certain degree.

0010 Furthermore, the optical writing head according to claim 4 is the optical writing head according to any one of claims 1 to 3. , the traveling direction of the member to be written at the contact portion of the substrate with the member to be written; Chamfer the board so that the downstream part makes a large angle with the surface of the member to be written. It is characterized by the following.

[0011] Further, in the optical writing head according to claim 5, in claim 4, the angle is set to 10 to 50. It is characterized by a certain degree.

0012 Furthermore, in the optical writing head according to claim 6, in claim 1, the optical writing head is configured such that the substrate is The feature is that the entire body is bent so that the side that comes into contact with the writing member has a convex shape. There is.

[0013]

[Effect]

According to the optical writing head of the present invention having such a configuration, the writing target member on the substrate and The contact part is formed into a convex curved shape at a position biased towards one end of this board. As a result, it is possible to obtain good contact with the writing target, and a good quality stamp can be obtained. Able to do kanji.

[0014]

【Example】

The present invention will be explained below with reference to embodiments shown in the drawings.

[0015] FIG. 1 shows a first embodiment of the present invention, in which one of the optical writing heads is shown in FIG. LED array head substrate (fiber array plate: FAP) 11 as an example It consists of a flat glass plate, and is made from a relatively large block-shaped material that is rolled into a thin plate. It is cut out with a chair.

[0016] One end side of the substrate 11 in the sub-scanning direction (horizontal direction in the figure) extends in the direction of arrow A. On the surface of the belt-shaped photoreceptor 12, which is an example of a moving belt-shaped member to be written on, Contact is placed. That is, the contact portion with the surface of the belt-shaped photoreceptor 12 is It is provided biased towards the end of the plate 11.

[0017] An optical fiber bundle 13 is attached to the contact portion of the substrate 11 with the belt-shaped photoreceptor 12. These optical fibers are buried in rows in the main scanning direction to form a light guide. The LED array chip 1 is placed so as to face the light incident side, which is the upper side of the bundle 13 in the figure. 4 is mounted on the substrate 11 using solder bumps or the like. This LED array The chip 14 is connected to the drive driver IC chip 15 through a predetermined conductor pattern. It is connected to the wiring pattern 16 and the IC power supply pattern 17. And before The light emitted from the light emitting part of the LED array chip 14 is transmitted to the optical fiber bundle 13. The image is formed on the belt-shaped photoreceptor 12 through the image, and an electrostatic latent image corresponding to the image is written. You will be killed.

[0018] Further, a belt at a contact portion of the substrate 11 with the belt-shaped photoreceptor 12 is provided. At one end edge (left edge in the figure) on the downstream side in the running direction of the shaped photoreceptor 12, a constant Chamfering is applied over the range. The surface 11a of this chamfered portion and the front At the intersection with the upstream entrance surface (bottom surface) 11b of the belt-shaped photoreceptor 12 in the running direction, , a smooth convex curved surface 11c is formed, and this convex curved surface 11c is The inner surface of the belt-shaped photoreceptor 12 is contacted. At this time, the substrate 11 The entrance angle θ between the upstream entrance surface 11b and the inner surface of the belt-shaped photoreceptor 12 is For example, it is set to a small angle below a certain value, such as 3 to 15 degrees. . This entrance angle θ changes the contact angle of the substrate 11 with the belt-shaped photoreceptor 12. adjusted by. Also, at this time, the belt-shaped photoreceptor 12 is downstream in the running direction. The surface 11a of the chamfered portion of the side portion is, for example, For example, the relief angle θ' is greater than a certain value, such as 10 to 50 degrees.

[0019] In this embodiment having such a configuration, the belt-shaped photoreceptor 1 of the substrate 11 is The contact portion to the surface of the substrate 11 is biased toward the end of the substrate 11, and A smooth photoconductor contact area can be created in this area with only a slight chamfering process. Therefore, good contact with the belt-shaped photoreceptor 12 can be obtained at low cost. Become. In particular, the upstream entrance surface 11b of the substrate 11 and the inner surface of the belt-shaped photoreceptor 12 Since the entrance angle θ between the Deformations such as waving caused by rows are gradually absorbed, and therefore the exposed area The contact condition is now stabilized.

[0020] At this time, the contact pressure of the substrate 11 can be adjusted by adjusting the curvature of the contact surface. It gradually increases from the entrance side on the side where exposure starts, and reaches its maximum in the area where exposure is performed. It is. i.e. the upstream inlet side part that initiates the contact and the downstream part that ends the contact. In each of the relief side parts, the curvature is set to 0, and A predetermined radius of curvature is set in the middle portion. The radius of curvature at this time is , you can set it to a constant value over the entire area, or you can set the curvature of the part that touches the plane to a small value. It is also possible to set the curvature of the comb and the exposed part to be large. . Also, if the curvature changes along a hyperbola, an extremely smooth contact surface can be created. A surface is obtained.

[0021] In addition, FIG. 2 shows another embodiment of the present invention. The substrate 21 is sliced into thin plates from a large block material. The entire structure is bent so that the surface facing the root-shaped photoreceptor 12 has a convex shape. The bending process of the substrate 21 is performed by placing the flat substrate in a high-temperature mold and performing a predetermined forming process. This is done by applying a process. The curvature of each part of the board does not have to be constant; It is also possible to make it into various shapes such as the shape of a pot or the bottom of a pot.

[0022] Note that the pads for mounting the conductive pattern and LED array chip are thin. Formed using a film process and mounted with flip-chip type LED array chips has been done. A driver for driving this LED array chip with any conductive pattern. The driver IC may also be mounted in a flip-chip format at the same time. Compare glass sheets By bending the glass with a large radius to reduce the amount of deformation of the glass, alignment of fiber bundles and substrate It can be processed while maintaining the overall flatness.

[0023] In addition, as another example, a conductor pattern is formed on the surface of a flat substrate by a thin film method. One possible method is to form a solder resist pattern and then bend the board. Ru.

[0024] According to this method, film formation and photoprocessing can be performed on a flat surface. Therefore, there is an advantage that the process is simplified.

[0025] In this case, choose a material with a high melting point for the metal wiring or solder resist pattern. It is necessary to In other words, a pattern is formed using a metal with a high melting point and low film stress. In addition, it is preferable to form a solder resist layer made of glass or inorganic material.

[0026] Yet another example is a substrate that is first bent or cut into a curved shape. A flexible printed circuit board (FPC) with a pattern formed on the inside of the , on which an LED array chip or the like may be mounted.

[0027] The flexible printed circuit board has a continuous pattern formed on a long film. It can be manufactured cheaply and in large quantities by cutting it at the final stage. , this flexible printed circuit board can be attached accurately to the inside of a curved board. I can do that.

[0028] By the way, when using a flexible printed circuit board as a mounting board, the pattern Accuracy is a key issue. In other words, the base fill of flexible printed circuit board Polyimide is usually used for the film, but it has a large coefficient of thermal expansion and cannot be heated to high temperatures. Dimensional stability is also poor when exposed to stress or simulated stress.

[0029] Therefore, as a countermeasure to this problem, a flexible printed circuit board described below is used. This flexible printed circuit board is double-sided and is used as a fiber array plate (FAP). Leave the copper foil on the side to be connected, except for the part that also allows light to pass through. This allows the LED array chip to The back side of the pad also has a solid copper pattern. And at least the fiber array - Make the thickness of the copper foil on the side that will be bonded to the plate thicker than the thickness of the base film. centre Pass the 5V and ground patterns in the longitudinal direction of the fiber array plate, and Increase the width of the ring. Double-sided flexible printed board with extremely high area ratio of copper foil By using a board, dimensional accuracy is ensured, and the 5V current pattern and ground pattern It also has the effect of reducing voltage drop by lowering the electrical resistance of the conductor.

[0030] The material of the fiber array plate is glass fibers made of glass. In addition to fixed types, there are also glass fibers fixed with resin and fiber It is also possible to use a substrate in which both sides are made of plastic.

[0031] In the second embodiment as well, as in the first embodiment described above, the substrate 21 is A smooth contact portion with the photoconductor 12 is formed by simply bending the surface, Good contact with the belt-shaped photoreceptor 12 can be obtained at low cost.

[0032] Note that the present invention is not limited to the above-mentioned embodiments, and can be modified as necessary. Various changes are possible.

[0033]

[Effect of the idea]

As explained above, the present invention applies slight chamfering or bending to the board. By this, a smooth curved surface is formed at the contact area with the writing target member, so that the writing target part Good contact with materials can be obtained at low cost, and clear images can be exposed with a simple configuration. I can.

[Brief explanation of drawings]

FIG. 1 is a side view showing an LED array head in a first embodiment of the present invention.

FIG. 2 is a side view showing an LED array head in a second embodiment of the present invention.

[Figure 3] Side view showing a conventional LED array head

[Explanation of symbols]

11, 21 Substrate 12 Belt-shaped photoreceptor 13 Optical fiber bundle 14 LED array chip

Claims (6)

[Scope of utility model registration request] 1. A substrate disposed in contact with a belt-shaped member to be written, and optical fibers embedded in an aligned state in a contact portion of the substrate with the member to be written so as to constitute a light guiding portion. An optical writing head comprising: a bundle of optical writing heads, characterized in that a contact portion of the substrate with a member to be written is formed in a convex curved shape at a position biased toward one end of the substrate. write head. 2. A portion of the substrate in contact with the member to be written, on the upstream side in the traveling direction of the member to be written, forms a small angle of less than a certain value with respect to the surface of the member to be written. 2. The optical writing head according to claim 1, wherein the substrate is arranged at an angle. 3. The optical writing head according to claim 2, wherein the angle is 3 to 15 degrees. 4. The substrate is chamfered so that a downstream portion of the contact portion of the substrate with the writing target member in the traveling direction of the writing target member forms a large angle with respect to the surface of the writing target member. The optical writing head according to any one of claims 1 to 3, characterized in that: 5. The optical writing head according to claim 4, wherein the angle is 10 to 50 degrees. 6. The optical writing head according to claim 1, wherein the entire substrate is bent so that the side that contacts the writing target member has a convex shape.