JPH08169138A - Imaging apparatus - Google Patents

Abstract

PURPOSE: To provide an imaging apparatus in which a latent image of high image quality can be accurately formed on a photosensitive element or an accurate electric signal corresponding to external image information can be generated on a solid state imaging element array. CONSTITUTION: An imaging apparatus comprises a lens plate 3a for linearly arraying and supporting a plurality of lenses 3b at a predetermined interval, and a base plate 1 for linearly arraying and mounting many image element arrays 2 to be so fixed that the lenses 3b and the arrays 2 are corresponded by 1 to 1, wherein each lens 3b is provided with a tapered part 3c and a template 4 having a diameter smaller than the maximum diameter of the lenses 3b and a hole H to be inserted with the part 3c of each lens 3b is disposed on the plate 3a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus used in an image forming apparatus such as an optical printer head or an image reading apparatus such as an image sensor.

[0002]

2. Description of the Related Art A conventional image forming apparatus, for example, an image forming apparatus used in an image forming apparatus such as an optical printer head, usually has a lens made of a resin such as polycarbonate in which a plurality of lenses are linearly arranged and supported at predetermined intervals. The plate and the base plate made of aluminum oxide sintered body or glass in which a large number of light emitting diode element arrays are linearly mounted are arranged so that each lens and each light emitting diode element array have a one-to-one correspondence. It has a fixed structure, and each light emitting diode element of each light emitting diode element array is caused to selectively emit light in response to an external electrical signal, and the light emitted by the light emitting diode element is passed through a lens. An image is formed on an external photoconductor, and a latent image is formed on the photoconductor to function as an image forming apparatus.

A light-emitting diode element array linearly arranged and mounted on the base plate generally has 64 light-emitting diode elements linearly arranged therein, which is suitable for a B4 size image forming apparatus. When used, the 32 light emitting diode element arrays are mounted on the base plate so that each of the 32 light emitting diode element arrays has a one-to-one correspondence with each lens.

Further, when each lens supported by the lens plate and each light emitting diode element array mounted on the base plate are displaced from each other, bleeding, white lines, black lines, etc. are formed on the image formed on the surface of the photoconductor. Therefore, it is impossible to form a clear and accurate latent image due to the above-mentioned problem. Therefore, it is necessary to align each lens and each light-emitting diode element array with extremely high accuracy.

Further, in each lens, a plurality of holes are linearly formed in the lens plate, and the lenses are adhered and fixed with an adhesive made of epoxy resin or the like so as to close the holes. Are arranged in a straight line.

[0006]

However, in this conventional image device, the lens plate is generally flat, and when the lens is adhered and fixed to the lens plate via the adhesive agent made of epoxy resin, the adhesive agent is used. Since heat curing at 150 ° C must be applied for about 1 hour to heat-harden, it takes a long time to bond and fix, and because the holes and holes in the lens and the plate have variations in the processing accuracy, the lens can be attached to the lens plate. When adhesively fixing, the lens fixing position is likely to be displaced, and when the lens is displaced, it is impossible to properly form the light emitted by each light emitting diode element array on the external photoconductor through the lens. However, there is a drawback that a clear and accurate latent image cannot be formed on the surface of the photoconductor.

In the above-mentioned embodiments, the image device used in the image forming apparatus such as the optical printer head has been described as an example, but it is used in the image reading apparatus such as the image sensor using the solid-state image sensor array. The image device to be used has the same drawback.

[0008]

SUMMARY OF THE INVENTION The present invention has been devised in view of the above-mentioned drawbacks, and an object thereof is to irradiate the surface of a photoconductor with light emitted from a light emitting diode element through a lens to accurately form a latent image of high image quality on the photoconductor. Or an image device capable of accurately forming an external image information on a solid-state image sensor array via a lens and generating an accurate electric signal corresponding to the external image information on the solid-state image sensor array. To provide.

[0009]

According to the present invention, a lens plate for linearly arranging and supporting a plurality of lenses at predetermined intervals and a base plate on which a large number of image element arrays are linearly arranged and mounted are provided for each lens. An image device fixed side by side so that each image element array has a one-to-one correspondence,
The lens is characterized in that a tapered portion is provided and a template having a hole smaller than the maximum diameter of the lens and having a hole into which the tapered portion of the lens is inserted is disposed on the lens plate.

Further, the present invention is characterized in that the base plate, the lens plate and the template have the same thermal expansion coefficient.

Further, in the present invention, the thermal expansion coefficients of the base plate, the lens plate and the template are −3 × 10 ⁻⁶ / ° C.
It is characterized in that it is set to 1 × 10 ⁻⁶ / ° C. (150 to 250 ° C.).

[0012]

According to the imaging apparatus of the present invention, the lens is provided with the tapered portion, and the template having the hole into which the tapered portion of the lens is inserted is arranged on the lens plate with a diameter smaller than the maximum diameter of the lens. If you insert the tapered part of the lens into the hole of the template from, the center position of each lens will be regulated extremely accurately even if there is some variation in the outer diameter of the lens and the diameter of the hole of the template depending on the template, As a result, the lens can be extremely accurately opposed to the image element array,
As a result, when used as an image forming apparatus such as an optical printer head, the light emitted from the light emitting diode element can be accurately irradiated onto the surface of the photoconductor through the lens to accurately form a latent image with high image quality on the photoconductor. In addition, when used as an image reading device, it is possible to accurately form an image of external image information on a solid-state image sensor array via a lens and generate an accurate electrical signal corresponding to the external image information on the solid-state image sensor array. it can.

According to the image device of the present invention, the coefficient of thermal expansion of the lens plate for arranging and supporting a plurality of lenses, the base plate on which a large number of image element arrays are mounted, and the template for restricting the position of each lens are the same, or −3 ×
If the coefficient of thermal expansion is set to 10 ^-6 / ℃ ~ 1 × 10 ^-6 / ℃ (150 ~ 250 ℃), heat will be applied to the lens plate, base plate and template when used as an image forming device or image reading device. Even if applied, each of them undergoes the same amount of thermal expansion, or each of them hardly undergoes thermal expansion, and as a result, the image element array can always be accurately opposed to the lens, whereby an image forming apparatus such as an optical printer head. When used as an image reading device, it can accurately irradiate the photoconductor surface with light emitted from the light emitting diode element through the lens to accurately form a latent image with high image quality on the photoconductor. , The external image information can be accurately formed on the solid-state image sensor array through the lens, and the solid-state image sensor array can generate an accurate electric signal corresponding to the external image information. .

[0014]

The present invention will now be described in detail with reference to the accompanying drawings. 1 to 3 show an embodiment in which the image device of the present invention is adopted in an optical printer head as an image forming device, 1 is a base plate, 2 is a light emitting diode element array, and 3 is a lens member.

The base plate 1 is made of, for example, a material having a coefficient of thermal expansion of −3 × 10 ⁻⁶ / ° C. to 1 × 10 ⁻⁶ / ° C. (150 to 250 ° C.), specifically, a carbon fiber reinforced liquid crystal polymer or the like. A plurality of light emitting diode element arrays 2 are linearly arranged and mounted on the upper surface thereof.

The base plate 1 acts as a supporting member for supporting the light emitting diode element array 2, and is formed into a predetermined shape by adopting an injection molding method.

Further, the light emitting diode element array 2 in which the base plate 1 is arranged and mounted comprises a plurality of light emitting diode elements 2a, and the light emitting diode elements 2a individually and selectively emit light in response to an external electric signal, By irradiating the surface of the photoconductor P with the emitted light, a latent image for forming an image is formed on the photoconductor P.

The light emitting diode element array 2 arranged and mounted on the base plate 1 is composed of a plurality of light emitting diode elements 2a. The light emitting diode elements 2a selectively emit light in response to an external electric signal to emit light. By irradiating the surface of the photoconductor P with the generated light, a latent image for forming an image is formed on the photoconductor P.

The light emitting diode element 2a is a GaAsP type, Ga
P-based light-emitting diodes are used, for example, in the case of a GaAsP-based light-emitting diodes, as well as heating to a high temperature the GaAs substrate at furnace First AsH ₃ and (arsine) PH ₃ and (Hosuhin) Ga (gallium ) Is contacted with a gas to grow a single crystal of n-type semiconductor GaAsP (gallium-arsenic-phosphorus) on the substrate surface, and then Si ₃ is grown on the GaAsP single crystal surface.
A windowed film of N ₄ (silicon nitride) is deposited, and Zn (zinc) gas is exposed to the window to form an n-type semiconductor GaAsP.
Zn is diffused into a part of the single crystal to form a p-type semiconductor, and pn
It is formed by providing a bond.

In the case of an optical printer head of B4 size, the light emitting diode elements 2a are 2048 (8 per 1 mm).
Are arranged linearly, and specifically, a light emitting diode element array in which 64 light emitting diode elements 2a are one unit
32 light emitting diode elements 2a are linearly arranged, and thus 2048 light emitting diode elements 2a are arranged and mounted on the base plate 1.

Further, the base plate 1 on which the light emitting diode element array 2 is mounted in an array is provided with a lens member 3 on its upper part at a constant distance.
Is composed of a lens plate 3a in which a plurality of holes are linearly arranged and a lens 3b attached to the lens plate 3a so as to close the holes.

The lens plate 3a of the lens member 3 acts as a support member for supporting the plurality of lenses 3b at a predetermined interval, and the holes allow the light emitted from each light emitting diode element 2a of the light emitting diode element array 2 to pass through the lens 3b. It has the function of permeating to.

The lens plate 3a is formed of, for example, a material having a coefficient of thermal expansion of −3 × 10 ⁻⁶ / ° C. to 1 × 10 ⁻⁶ / ° C. (150 to 250 ° C.), specifically, a liquid crystal polymer or the like. There is.

Further, each lens 3b supported by the lens plate 3a has a function of irradiating the surface of the photoconductor P with light emitted from each light emitting diode element 2a, and a transparent resin such as an acrylic resin or a polycarbonate resin, or a glass or the like. A lens formed of the transparent inorganic material is preferably used.

Further, the lens 3b has a tapered portion 3c on the outer peripheral portion of the lower surface thereof, and as shown in FIG. 3, the lens 3b has a diameter smaller than the maximum diameter of the lens 3b and a tapered portion of the lens 3b. A template 4 having a hole H into which 3c is inserted is arranged.

The template 4 functions to regulate the position of each lens 3b and to accurately align the center position of the lens 3b with a predetermined position of the lens plate 3a. The tapered portion 3c of the lens 3b is provided in the hole H of the template 4. If inserted, each lens 3b
The center position of the lens can be extremely accurately aligned with the template 4 at a predetermined position on the lens plate 3a even if the outer dimensions of the lens 3b and the diameter of the hole H of the template 4 vary. As a result, lens 3b
The light-emitting diode element array 2 can be made to face each other very accurately, whereby the light emitted from the light-emitting diode element 2a is accurately irradiated onto the surface of the photoconductor P via the lens 3b, and the photoconductor P is laid with a high-quality latent image. Can be accurately formed.

The template 4 is made of, for example, a material having a coefficient of thermal expansion of −3 × 10 ⁻⁶ / ° C. to 1 × 10 ⁻⁶ / ° C. (150 to 250 ° C.), specifically, a carbon fiber reinforced liquid crystal polymer or Invar. It is made of so-called steel or the like.

Further, when the template 4 is provided with a notch around the hole H, a spring property is generated around the hole H of the template 4, and when the tapered portion 3c of the lens 3b is inserted into the hole H of the template 4, the lens 4 No excessive force acts on 3b to cause damage. Therefore, it is preferable that the template 4 has a cutout around the hole H.

Furthermore, the light emitting diode element array 2
The base plate 1 on which is mounted and the lens plate 3a having the plurality of lenses 3b are fixed to the spacers 5 formed of glass epoxy resin or the like, so that each light emitting diode element array 2 and each lens 3a are predetermined. They are installed side by side with one-to-one correspondence over a distance.

The spacer 5 has a first alignment reference surface 5a on the upper portion thereof and a second alignment reference surface 5b on the lower portion thereof, and the first alignment reference surface 5a of the spacer 5 has a lower surface of the lens plate 3a. By fixing the outer peripheral portion of the upper surface of the base plate 1 to the second alignment reference surface 5b so that each light emitting diode element array 2 and each lens 3a are in a one-to-one correspondence with a predetermined distance between them. Has become. still,
A lens plate 3a for arraying and supporting a plurality of lenses 3b which are fixed together by a predetermined distance via the spacer 5, a base plate 1 on which a large number of light emitting diode element arrays 2 are mounted, and a template for regulating the position of each lens 3b. Four
If the coefficients of thermal expansion are the same, when used as an image forming apparatus, even if heat is applied to each of the lens plate 3a, the base plate 1 and the template 4 and the thermal expansion of each of them is the same, As a result, each light emitting diode element array 2 can always be accurately opposed to each lens 3b. As a result, the light emitting diode element 2a
It is possible to accurately irradiate the surface of the photoconductor P with the light emitted from the photoconductor P through the lens 3b to form a latent image with high image quality on the photoconductor P accurately. Therefore, it is preferable that all of the lens plate 3a, the base plate 1 and the template 4 have the same thermal expansion coefficient.

The coefficient of thermal expansion of each of the lens plate 3a, the base plate 1 and the template 4 is set to −3 × 10.
^-6 / ℃ ~ 1 × 10 ^-6 / ℃ (150 ~ 250 ℃) When used as an image forming apparatus, even if heat is applied to each of the lens plate 3a, the base plate 1 and the template 4 Almost no thermal expansion occurs, and as a result, each light-emitting diode element array 2 always faces each lens 3b accurately, and the light emitted from the light-emitting diode element 2a is also accurately transferred to the surface of the photoconductor P through the lens 3b. To the photoconductor P
It is possible to accurately form a latent image with high image quality. Therefore, the lens plate 3a and the base plate 1
And template 4 has a coefficient of thermal expansion of −3 × 10
It is preferably ^-6 / ° C to 1 × 10 ^-6 / ° C (150 to 250 ° C).

Thus, according to the image device of the present invention, a predetermined electric power is applied to each of the light emitting diode elements 2a arranged and mounted on the base plate 1 to cause each of the light emitting diode elements 2a to individually and selectively emit light. The light emitted from the light emitting diode element 2a is focused on the surface of the external photoconductor P via the lens 3b to form a predetermined latent image on the photoconductor P, thereby functioning as an image forming apparatus.

Further, the present invention is not limited to the above-mentioned embodiments, and various modifications can be made without departing from the scope of the present invention. For example, in the above-mentioned embodiments, the optical printer head or the like can be changed. Although the description has been given by taking the case where the light emitting diode element array is used as an image forming apparatus as an example, the light emitting diode element array can be used as an image reading apparatus such as an image sensor by changing the solid state image pickup element array.

[0034]

According to the image device of the present invention, the tapered portion is provided on the lens and the template having the hole into which the tapered portion of the lens is inserted is arranged on the lens plate with a diameter smaller than the maximum diameter of the lens. Therefore, if the tapered portion of the lens is inserted into the hole of the template, the center position of each lens will be regulated extremely accurately even if there is some variation in the lens outside dimension and template hole diameter depending on the template. As a result, the lens can be made to face the image element array extremely accurately, and when used as an image forming apparatus such as an optical printer head, the light emitted from the light emitting diode element is accurately transmitted to the photoconductor surface through the lens. It is possible to accurately form a latent image with high image quality on the photoreceptor by irradiating the If you use, it can be allowed to accurately formed on the solid-state imaging device array through the lens external image information, to generate a precise electric signal corresponding to the external image information on the solid-state imaging device array.

Further, according to the image device of the present invention, the thermal expansion coefficient of the lens plate for arranging and supporting a plurality of lenses, the base plate on which a large number of image element arrays are mounted, and the template for controlling the position of each lens are the same, or −3 ×
If the coefficient of thermal expansion is set to 10 ^-6 / ℃ ~ 1 × 10 ^-6 / ℃ (150 ~ 250 ℃), heat will be applied to the lens plate, base plate and template when used as an image forming device or image reading device. Even if applied, each of them undergoes the same amount of thermal expansion, or each of them hardly undergoes thermal expansion, and as a result, the image element array can always be accurately opposed to the lens, whereby an image forming apparatus such as an optical printer head. When used as an image reading device, it can accurately irradiate the photoconductor surface with light emitted from the light emitting diode element through the lens to accurately form a latent image with high image quality on the photoconductor. , The external image information can be accurately formed on the solid-state image sensor array through the lens, and the solid-state image sensor array can generate an accurate electric signal corresponding to the external image information. .

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing an embodiment in which an image device of the present invention is used in an optical printer head as an image forming device.

2 is a cross-sectional view of the optical printer head shown in FIG.

FIG. 3 is an enlarged plan view of an essential part of the optical printer head shown in FIG.

[Explanation of symbols]

 1 ... Base plate 2 ... Light emitting diode element array 2a ... Light emitting diode element 3 ... Lens member 3a Lens plate 3b・ Lens 3c ・ ・ ・ ・ ・ Tapered part of lens 4 ・ ・ ・ Template 5 ・ ・ ・ ・ Spacer P ・ ・ ・ ・ Photoconductor H ・ ・ ・ ・ Hole

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location H04N 1/028 Z 1/036 A

Claims (3)

[Claims] 1. A lens plate for linearly arranging and supporting a plurality of lenses at predetermined intervals, and a base plate on which a large number of image element arrays are linearly arranged and mounted. An image device fixed side by side so as to correspond to a pair, wherein a tapered portion is provided on the lens, and a lens plate has a hole having a diameter smaller than the maximum diameter of the lens and into which the tapered portion of the lens is inserted. An image device having a template. 2. The image device according to claim 1, wherein the base plate, the lens plate and the template have the same coefficient of thermal expansion. 3. The base plate, the lens plate, and the template have a coefficient of thermal expansion of −3 × 10 ⁻⁶ / ° C. to 1 × 10 ⁻⁶ / ° C.
The image device according to claim 1, wherein the image device has a temperature of 150 ° C (150 to 250 ° C).