JPS62230255A - Contact type image sensor unit - Google Patents

Abstract

PURPOSE:To attain multi-gradation by arranging a shutter transmitting/shutting optionally a light beam from an original face between a SELFOC lens array and the original face so as to reduce the optical interference between adjacent photosensitive elements. CONSTITUTION:An original is placed on an original glass 7 while the written face is directed downward and lighted by a transparent liquid crystal electrode plate 9 by the lighting of an LED array 8. Then only the required light is transmitted through the SELFOC lens array 11 by a liquid crystal shutter 10 and the image is formed in the photosensitive element section 13 in the contact image sensor 12. The electrode pattern of the liquid crystal shutter 10 is arranged similarly as that of the photosensitive element section 13. Further, a signal is outputted sequentially from one by one photosensitive element, not outputted in the lump from all the elements, and multi-gradation is attained easily without interference of optical signals of adjacent photosensitive elements.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a contact type image sensor unit used in an image input device of office automation equipment such as a facsimile or a copying machine.

BACKGROUND OF THE INVENTION In recent years, there has been remarkable progress in office automation equipment such as facsimile machines and copying machines.

Under these circumstances, recently there has been an increasing demand for smaller size and higher performance image input devices for OA equipment, and close-contact image sensors are attracting attention as image sensors used in these image input devices.

This contact type image sensor does not require a large-scale optical system and has an elongated shape with the same dimensions as the original.

A contact image sensor unit manufactured using this contact image sensor had the configuration shown in FIG. 4.

Here, 1 is an original glass surface, and the original surface is placed on the upper surface of this original glass surface 1 with the original surface facing downward. Reference numeral 2 denotes an IJD array.The LED array 2 illuminates the document surface, and the selfox lens array 3 forms an image of the document surface on the photosensitive element section 6 in the contact image sensor 4. The unit 5 converts the optical information on the document surface into an electrical signal.

Problems to be Solved by the Invention However, in the contact type image sensor unit having the above-mentioned configuration, for example, when one unit of photosensitive element is white on the document surface, 3 bases are required.

Even if the adjacent element is black on the document surface, the white signal, which is originally the information of the adjacent element, is mixed, resulting in a black signal, as shown in Figure 6. "Corresponding to photosensitive elements '5a and 5C."

Even if the information on the document surface is black, it corresponds to the photosensitive element 5b. - When the white light of the information enters the Selfox lens array, the information of the percentage white emission of B is mixed with the black information of the photosensitive elements 5a and 6C. Resulting in.

Due to the nature of Selfox Lens Array 3, this proportion of contamination cannot currently be avoided. This is a very important problem when performing multi-tone signal processing.

Means for Solving the Problems In order to solve the above-mentioned problems, the contact image sensor unit of the present invention has a structure between the Selfox lens array and the document surface that allows light from the document surface to be arbitrarily transmitted or blocked. The shutters are arranged so that

Function: The present invention satisfies the demand for multi-gradation by converting optical signals on the surface of a document into electrical signals without causing interference between optical signals from adjacent photosensitive elements using the above-described configuration.

It becomes something that can be done.

EXAMPLE An example of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic cross-sectional view of a contact type image sensor unit according to an embodiment of the present invention.

Reference numeral 7 denotes a document glass, and the document is placed face down on the upper surface of the document glass.Next, the LED array 8 emits light, which passes through the transparent liquid crystal electrode plate 9 and illuminates the document surface. Next, by applying the liquid crystal shutter 10, only the necessary I is transmitted through the Selfox lens array 11, and an image is formed on the photosensitive element section 13 in the contact type image sensor 12.

In this embodiment, a bipolar IC is used for the photosensitive element section 13, and a decoder circuit is built-in. The same decoder circuit is also used to drive the liquid crystal.

Further, the electrode pattern of the liquid crystal shutter 1Q is similar to the arrangement of the 5B/cm photosensitive element section 13.

This is illustrated in FIG. 2.

Information on the document surface is provided by photosensitive elements 13a and 13b.

130, black, white, black.

It should be noted here that the signals of the image sensor photosensitive elements do not output signals from all elements at the same time, but use signals from one element sequentially. In other words, only one element is operating at any given moment. Therefore, the liquid crystal sensor 1o is opened and closed so that only the optical signal from the document surface corresponding to the operating photosensitive element enters the Selfox lens array 11. As a result, as shown in the figure, the optical signal of the photosensitive element 131) is mixed with the photosensitive element 13a.
This means that the optical signal from the surface of the document enters without any light entering. That is, the optical signals on the document surface can be converted into electrical signals without interference between adjacent photosensitive elements, and multi-gradation can be easily achieved.

The electrical block diagram is shown in Figure 3.

14 is a start pulse (, sp) and a clock (GLK
) is a 6-page signal circuit for operating the decoder, 15 is a decoder circuit, 16 is a transparent liquid crystal plate, 1 is a photosensitive element section, and 18 is an amplifier circuit.

First, clock (CL, K) and start pulse (sp)
The input causes the signal circuit 14 to operate and the decoder circuit 15 to scan. As a result, the transparent liquid crystal plate 16 and the photosensitive element section 17 operate at corresponding locations. At that time, the photo-electrical conversion signal from the photosensitive element section 17 is input to the amplifier circuit 18, amplified, and output as a sensor output.

- Effects of the invention As described above, the contact image sensor unit of the present invention reduces optical interference between neighboring photosensitive elements by disposing the shutter between the document surface and the Selfox lens array, and It has an industrial value as it has the effect of creating gradations.

[Brief explanation of drawings]

'1,'', page 17 The figure is a schematic cross-sectional view of one embodiment of the contact type image sensor unit of the present invention, Figure 2 is an explanatory diagram showing the improvement effect of the present invention, and Figure 3 is an electrical block diagram of the same. , Fig. 4 is a schematic cross-sectional view of the conventional example, and Fig. 5 is an explanatory diagram showing the same problem. 7... Original glass, 8... I, ED array, 1°. ...LCD shutter, 11...
. . . Selfox lens array, 12 . . . Contact type image sensor, 13 . . . Photosensitive element section. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2 Figure 3 Figure 4 Figure 5

Claims (1)

[Claims] A contact image sensor, a Selfox lens array arranged so as to focus light from the original on the contact image sensor, and a sensor between the original and the Selfox lens array that allows light from the original to be transmitted or blocked as desired. A close-contact image sensor unit characterized by a shutter arranged so as to