JPH0836632A - Image input device - Google Patents

Abstract

PURPOSE:To make a linear image input device select two dropout colors with simple configuration and simple control. CONSTITUTION:A LED array 12 being a light source for a linear image input is made up of plural division arrays 101-10N and a 2-color light emitting element LED is adopted for LED elements 201-20n. Independent lighting color control is applied to each of the division arrays 101-10N based on a corresponding color selection control signal 14 from a color selection control circuit 13. Thus, a dropout color is selected independently for plural (N) areas on scanning lines.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image input device, and more particularly to a one-dimensional image input device used for a contact type image sensor for reading an image on a form.

[0002]

2. Description of the Related Art A conventional one-dimensional image input device of this type is
As shown in FIG. 2A, the form 6 is irradiated with light of a predetermined color from the monochromatic light emitting LED (light emitting diode) array 2 arranged in the main scanning direction with respect to the form 6 and serving as a light source. Semi-illuminated light of transparent glass 5 and lens 4
The image is input to the image input unit 3 via.

FIG. 2B shows a schematic block diagram of the one-dimensional image input device 1, and FIG. 2C shows a monochromatic light emission L.
The internal circuit diagram of the ED array 2 is shown. The monochromatic light emitting LED array 2 shown in these drawings has a plurality of monochromatic light emitting LED elements 21 to 2x arranged along a scanning line, and a lighting signal is output from a lighting control circuit 7 via a lighting control line 8. L
By supplying to the ED elements 21 to 2x, all of these single color light emitting LED elements 21 to 2x can be turned on at the same time.

In such a structure, the image scanned by the scanning line 10 on the form 6 shown in FIG. 3 (A) has a high reflectance due to the spectral sensitivity characteristic with respect to an LED of the same color as the monochromatic light source, for example, a reddish LED. Character frame 11 printed in red
The background color becomes a dropout color and is removed and the image is input.

When the color of the dropout needs to be of two colors, for example, Japanese Patent Laid-Open No. 61-239379.
It is necessary to use a filter as described in Japanese Patent Laid-Open Publication No. 1994-126, to switch this, or to switch the emission color of the light source.

[0006]

As described above, in the conventional image input device, when it is necessary to set the dropout color to two or more colors, the filter is switched during the scanning of one line, and the light source is changed. However, there is a drawback that the control becomes complicated because it is necessary to switch the colors.

An object of the present invention is to provide an image input device having a very simple structure and capable of dropping out a plurality of colors with simple control.

[0008]

According to the present invention, there is provided an image input device having a light emitting element array in which light emitting elements are arranged in an array in a scanning direction on the form as an irradiation light source for reading an image of the form. And each of the light emitting elements comprises a set of a first light emitting element that emits a first color and a second light emitting element that emits a second color. An image input device is provided which is provided with a control means for performing the selective lighting control.

[0009]

Each element forming the light emitting element array is a two-color light emitting element, and a plurality of these light emitting element arrays are arranged on the scanning line to select the emission color for each array.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing an embodiment of the present invention, and the same parts as those in FIG. 2 are designated by the same reference numerals. Figure 1 (A)
Referring to FIG. 3, the structure is shown, and the part different from the conventional example is the LED array 12 which is an irradiation light source. As shown in (B), the LED array 12 is divided into N (N is an integer of 2 or more) of a plurality of arrays 101 to 10N in the scanning line direction.
The control signals of the color selection control lines 14 respectively derived from the color selection control circuit 13 are respectively supplied.

The structure of 101 to 10N of each array is shown in FIG.
As shown as a representative of the array 101 in (C), each constituent LED element 201 to 20n (n is an integer of 2 or more) has a different emission spectrum from each other. It consists of color emitting LEDs.

Color selection control line 1 from the color selection control circuit 13
Each of the two-color light emitting LEDs 201 to 20n is capable of selectively emitting a color of one of the systems simultaneously by the positive phase signal of the control signal of No. 4 and the negative phase signal of the inverter 200.

Therefore, as shown in FIG.
When it is necessary to divide the area in the scanning direction corresponding to the upper scanning line 10 into N (two in the figure) different color dropouts, the LED array 12 is divided into N corresponding areas (two; 101; Then, if the color selection control signal is controlled for each array, then two color dropouts can be selected in each area.

Here, LEs constituting the LED array 12
Assuming that the required total number of D elements is x (the required number of elements on one scanning line), the relationship between these x, N, and n is x = N × n, so for example, x = 32, N = 16 In some cases, n becomes 2, and it becomes possible to divide the scanning line area in the main scanning direction of the one-dimensional image input device 1 into 16 and select the LED lighting color for each area.

[0016]

As described above, according to the present invention, by configuring each constituent element of the LED array with LED elements of two system colors, two different system dropout colors can be easily realized and the array By dividing and dividing and controlling the lighting color for each array, it is possible to set different dropout colors independently in a plurality of regions on the scanning line. Further, it is possible to switch the light source colors of two systems for each line in the main scanning direction and input an image.

[Brief description of drawings]

1A and 1B show a configuration of an embodiment of the present invention, in which FIG. 1A is a diagram showing a structure, FIG. 1B is a block diagram, and FIG. 1C is a circuit diagram.

2A and 2B show a conventional image input device, wherein FIG. 2A is a diagram showing a structure, FIG. 2B is a block diagram, and FIG. 2C is a circuit diagram.

FIG. 3 is a diagram showing a relationship between a scan line on a form and a dropout color in a conventional method and in the present invention in comparison.

[Explanation of symbols]

 1 Image Input Device 3 Image Input Unit 4 Lens 5 Transparent Glass 6 Form 12 LED Array 13 Color Selection Control Unit 14 Color Selection Control Line 101-10N Divided Array 200 Inverter 201-20n Two-Color Light Emitting LED Element

Claims (3)

[Claims] 1. An image input device having a light emitting element array in which light emitting elements are arranged in an array in a scanning direction on the form as an irradiation light source for reading an image of the form, each of the light emitting elements being A control unit is provided which includes a set of a first light emitting element that emits a first color and a second light emitting element that emits a second color, and that controls the selective lighting of the first and second light emitting elements. An image input device characterized in that 2. The image input device according to claim 1, wherein a plurality of said light emitting element arrays are provided, and said control means is provided corresponding to these light emitting element arrays. 3. The image according to claim 1, wherein the first and second light emitting elements are light emitting diodes, and the first and second colors are red and blue colors, respectively. Input device.