JPH07175015A - Optical device and its production - Google Patents

Abstract

PURPOSE:To reduce the volume of a device and to lower the cost of assembling and adjusting the device relating to the contact type optical device to be used in fields of facsimiles, optical printers, etc., and a process for production of this device. CONSTITUTION:This optical device has a lens array on which an erecting real image is formed and plural pieces of approximately circular columnar rod lenses 21 having light shielding layer are arranged on a light transmissive substrate 11, a light receiving element array or light emitting element array 31 on the surface on the side opposite to the surface where the lens array is arranged, the light transmissive substrate 11 on which an IC for driving these elements is arranged, and a reflection surface 22 which reflects the rays progressing in this lens array. The lens array and the light receiving element array or light emitting element array 3 are so arranged that the erecting real image groups formed by the lens array are formed on the light receiving element array or light emitting element array 31 surface.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a contact type optical device used in the fields of facsimiles, optical printers and the like, and a method of manufacturing the same.

[0002]

2. Description of the Related Art Contact optical devices are currently used in facsimiles,
Used as an optical device for optical printers. In such an apparatus, for example, the length of a cylindrical rod lens having a refractive index distribution formed therein is adjusted so as to form a one-to-one erect real image, and this is placed between the substrates. It is a lens array arranged in one row or a plurality of rows, and is configured such that the erect real images of the individual lenses coincide with each other.

For example, focusing on an application example of a facsimile, an erect real image of a pattern drawn on a document arranged close to the lens array is on the opposite surface side of the lens array at a magnification of 1: 1. It is formed.

FIG. 5 shows an example in which this lens array is applied to a facsimile sensor. The rod lens 21 is a lens having a refractive index distribution, and the plurality of lenses are sandwiched between two substrates 12 and arranged in a line in a direction perpendicular to the paper surface. A document 61 is arranged on one side of the lens, and a sensor IC 3 for receiving the image forming light of the document is arranged on the opposite side.
1 is arranged. The substrate 14 on which the sensor ICs are arranged and the lens array are fixed to each other by a housing 81.

In this case, the distance between the document surface and the sensor is
About 20 mm to 60 mm, width 200-300 mm
It has an excellent feature that it can form an image of the original document in a short distance. Such a lens array is sold, for example, by Nippon Sheet Glass Co., Ltd. under the name of SELFOC lens array (registered trademark) (hereinafter abbreviated as SLA (registered trademark)).

Illumination of the original is not shown in the figure, but another illumination device illuminates the portion to be read.

On the other hand, in the case of application to an optical printer, the sensor IC portion becomes an LED array, and the photosensitive drum is arranged at a position corresponding to the original. Then, the image pattern emitted from the LED array is written on the photosensitive drum.

As described above, this SLA is 200 to 3
Since a real image having a wide area of 00 mm can be obtained at a distance of 20 to 60 mm, it has a feature of greatly contributing to downsizing of a facsimile and an optical printer.

[0009]

However, in this conventional example, the sensor IC or LED array, which is a light-receiving element array or a light-emitting element array, the substrate 14 provided with the electrical wiring for connecting these, and the SLA. They were provided separately, positioned in the housing 81 and assembled.

Therefore, there is a problem that the volume of the device becomes large, and it is necessary to assemble while finely adjusting the optical axis and the focus position of the SLA and the sensor IC or the LED array, which causes an assembly cost and an adjustment cost. I also had problems.

[0011]

In order to solve the above problems, according to the present invention, (a) a plurality of rod lenses having a substantially cylindrical shape on which an erect real image is formed and having a light shielding layer on the side surface thereof are formed on a transparent substrate. (B) The light-transmissive substrate on which a light-receiving element array or a light-emitting element array and ICs for driving these elements are arranged on the surface opposite to the surface on which the lens array is arranged, C) On the optical axis of the lens array,
A light-reflecting surface that reflects a light ray that has traveled through the lens array so that the light ray enters the light-receiving element array or the light-emitting element array, and (d) an erect real image group formed by the lens array is the light-receiving element. The lens array and the light receiving element array or the light emitting element array are arranged so that an image is formed on the surface of the element array or the light emitting element array, and an optical device having all of the above is manufactured.

[0012]

As described above, the optical device of the present invention does not require the housing as shown in the conventional example. Further, the substrate of the lens array can also be used as the substrate of the light receiving element array or the light emitting element array.

[0013]

EXAMPLES Examples of the present invention will be described below. FIG. 1 is a schematic configuration diagram of an embodiment of the present invention. A large number of cylindrical lenses 21 having a refractive index distribution in which the refractive index becomes smaller from the center to the outer peripheral portion and the lengths of which are adjusted so as to form an erect real image. And sandwiched between the non-translucent substrate 12 and arranged in parallel to each other,
A filler 25 having a light shielding function is filled in these gaps to form a gradient index lens array. The non-translucent substrate 12 can be used as necessary and does not have to be non-translucent. The cylindrical lens 21 has a side surface previously coated with a light-shielding layer. Further, one surface of the translucent substrate 11 may be coated with a light shielding layer.

A prism 23 having a reflecting surface 22 in which a groove reaching the substrate 11 is formed by cutting the substrate 12 and the lens array from the side of the substrate 12 is formed.
Are arranged. This reflecting surface is obtained by forming a metal film having a high reflectance such as aluminum.

Specifically, this prism is a columnar body made of acrylic resin, and has at least a surface contacting the bottom surface and one side surface of the groove and a surface having an oblique angle with respect to the optical axis of the lens array. And a surface having an oblique angle is vapor-deposited with aluminum to form a reflecting surface. Note that this angle is selected so that the light rays from the lens array enter the sensor IC 31 as described later.

Light rays from the image drawn on the original 61 travel along the optical axis 71. First, the gradient index lens 21
Through the prism 23, the reflecting surface 22 bends the direction of travel substantially at a right angle, passes through the transparent substrate 11, and enters the sensor IC 31 provided on the substrate 11. This sensor IC is, for example, a CCD element or the like.

When the prism is made of a resin material (for example, acrylic resin) having a refractive index of about 1.5, the translucent substrate is preferably a glass substrate having a refractive index of about 1.5.

Here, the length of the gradient index lens 21 is
The real image of the original image is formed so as to coincide with the incident surface of the sensor IC. The lens 21 is a product name: S manufactured by Nippon Sheet Glass Co., Ltd.
Produced using the same lens as the gradient index lens used for LA-20 (lens diameter: 1 mm, refractive index on optical axis n ₀ : 1.63, refractive index distribution constant √A: 0.44 (mm ^-1 )) is doing.

Specifically, the length of the lens is 8 mm, the distance from the lens to the original is about 3 mm, and the distance from the other surface of the lens to the sensor IC through the prism is about 4.5 mm. . The distance on the prism side is longer than that on the original side because the prism material and the material for forming the translucent substrate have a refractive index of about 1.5. This is because = 4.5 mm.

Further, the prism 23 is adhered by using an ultraviolet curable adhesive 24, and an adhesive having a refractive index of 1.5 is selected and used (specifically, manufactured by Kyoritsu Chemical Co., Ltd.). X8721). By adjusting the refractive indexes of the prism material, the substrate material, and the adhesive material in this way, light reflection at each interface is eliminated, and even if each surface is slightly rough, there is an advantage that light scattering is eliminated. have. The black filler between the lenses uses a silicone resin containing a black pigment. This is because the black pigment shields the light between the lenses.

FIG. 2 is a view showing the back side of the structure shown in FIG. The wiring 41 is formed on the transparent substrate 11, and the sensor IC 31, which is a light receiving element, is provided thereon.

FIG. 3 is a sectional optical path diagram of the structure shown in FIGS. Sensor IC 31 on wiring 41
Are fixed by solder bumps. This solder bump is generally used as a method for mounting a semiconductor IC, and solder on the electrode portion on the sensor IC is placed on it and pressed against the wiring 41 to raise the temperature to melt and fuse the solder. It is a thing.

Next, FIG. 4 shows a manufacturing process of an embodiment according to the present invention. This is the case when many optical devices are manufactured at once.

First, the translucent substrate 11 on which the wiring 41 is formed
And a non-translucent substrate 12 (for example, each size is 3
A large number of rod lenses 21 each having a refractive index distribution are sandwiched (Fig. 4a) with a 00 mm square and a plate thickness of 1 mm). The rod lenses 21 are arranged in parallel with each other. In this case, the thickness is about 4 mm and the size is about 30 mm square. Further, a black silicone resin is filled in the spaces between the lenses and the substrate, and the black silicone resin is bonded. The non-translucent substrate 12 can be used if necessary.

After that, a square groove 13 is formed by grinding with a diamond blade (FIG. 4b). This groove 13
Is formed by cutting the rod lens from the non-translucent substrate 12 side so as to reach the translucent substrate 11. Specifically, in this case, the depth is about 2.5 mm and the width is about 3 mm. In order to improve the flatness of the groove, first, the groove is dug with a coarse count blade (for example, No. 150), and then the groove surface is ground again with a fine count blade (for example, No. 400) to improve the flatness. The technique of raising can be used.

Subsequently, the prism 23 is embedded in the groove 13 (FIG. 4c). This prism is a column made of acrylic resin and has a surface in contact with the bottom surface and one side surface of the groove, and a surface having an oblique angle with respect to the optical axis of the lens array. Aluminum is vapor-deposited on the holding surface to make it a reflective surface. An ultraviolet curable resin 24 is used for bonding the prism.

Subsequently, the sensor IC 31 is bonded onto this structure (FIG. 4d). Solder bumps 42 are formed on the sensor ICs, and the solder bumps 42 are aligned and bonded onto the wirings 41. Finally, a dicing saw cuts and separates each optical device (FIG. 4e).

In the above embodiment, the case where the sensor IC is mounted has been described, but the present invention is not limited to this embodiment, and instead of the sensor IC, an LED array or an LD array which is a light emitting element is used. Or ICs for driving them at the same time may be arranged adjacent to each other. Further, as the reflecting surface, the case where the metal film is formed on the prism has been described, but this may be a mirror.

[0029]

As described above, the optical device according to the present invention does not require the housing as shown in the conventional example. Therefore, the size of the entire device can be compactly integrated.

The lens array substrate and the sensor IC
Alternatively, since it can be used also as an LED substrate, the cost of the optical device can be further reduced in combination with the fact that the above-mentioned housing is unnecessary. Further, the sensor IC and the LED array are two-dimensionally mounted on the substrate, and can be mounted inexpensively by utilizing the surface mounting technology already developed.

[Brief description of drawings]

FIG. 1 is a structural schematic view showing an embodiment of the present invention.

FIG. 2 is a schematic structural view showing the back surface side of FIG.

FIG. 3 is a sectional optical path diagram of FIG.

FIG. 4 is a diagram showing a manufacturing process of the present invention.

FIG. 5 is a structural diagram of a conventional contact image sensor.

[Explanation of symbols]

 11 Translucent Substrate 12 (Non-translucent) Substrate 13 Groove 14 Substrate Having Wiring 21 Cylindrical Gradient Distribution Lens 22 Reflecting Surface 23 Prism 24 Ultraviolet Curing Resin 25 Black Filler 31 Sensor IC (or LED Array) 41 Wiring 42 Solder Dump 51 Light Source 61 Original Document 71 Optical Axis 81 Housing

Claims (4)

[Claims] (A) A lens array in which a plurality of rod lenses having a substantially cylindrical shape on which an erect real image is formed and having a light-shielding layer on the side surface thereof are arranged on a transparent substrate, (b) the lens array A light receiving element array or a light emitting element array and the translucent substrate on which ICs for driving these elements are arranged on a surface opposite to the arranged surface; and (c) on the optical axis of the lens array, The light rays traveling through the lens array are
A reflection surface that reflects the light rays so as to enter the light receiving element array or the light emitting element array, and (d) an erect real image group formed by the lens array is formed on the light receiving element array or the light emitting element array surface. An optical device characterized in that the lens array and the light receiving element array or the light emitting element array are arranged so as to be imaged, and all of the above are provided. 2. The optical device according to claim 1, wherein
There is a groove that reaches the transparent substrate from the lens array, the reflective surface is the surface of a prism made of a transparent material having a surface oblique to the optical axis of the lens array,
An optical device in which the prism is arranged in the groove. 3. The optical device according to claim 1, wherein
An optical device in which an electrode formed on the light receiving element array or the light emitting element array and a wiring formation surface on the light transmissive substrate face each other and are in electrical contact with each other. 4. An electric wiring pattern (4) is provided on one side thereof.
A plurality of rod lenses (21) having a refractive index distribution inside and a light-shielding layer on the side surface are arranged in parallel on the surface opposite to the surface of the translucent substrate (11) on which 1) is formed. Arranging and fixing, (b) From the rod lens (21) side,
Providing a groove 13 reaching the translucent substrate (11),
(C) Step of fitting a prism (23) having a reflecting surface in the groove portion, (d) Rod lens so that an erect real image by the rod lens is formed on a light receiving element array or a light emitting element array described later. (21) a step of adjusting and cutting the length, (e) a step of connecting a light-receiving element array or a light-emitting element array on the electric wiring pattern (41), and all the above steps. Optical device manufacturing method.