JPH02108362A - Picture reader - Google Patents

Abstract

PURPOSE:To correctly detect an original width beforehand before an original picture is read and to confirm that original information is not present outside the read range by providing an original width detecting means to detect the original width at the original width regulating means of an original moving type picture reader. CONSTITUTION:Sliding resistors 2a and 2b are fixed to original platens 1a and 1b as the original regulation of a picture reader, the voltage is added to the resistors 2a and 2b and the original platens 1a and 1b are moved by matching to the width of the original. The original platens 1a and 1b are moved by matching to the width of the original and pinions 6a and 6b are rotated by the movement of racks 5a and 5b. The rotation angle is detected by rotary encoders 7a and 7b, the detecting output is sent to a picture processor 4, and based on the detecting output value, the original width is detected. Here, the output of the encoders 7a and 7b is converted to a digital signal by A/D conversions 3a and 3b, supplied to the picture processor 4 or supplied to the picture processor 4 directly as it is. The original width is correctly detected beforehand before the original picture is read by the original platens 1a and 1b.

Description

[Detailed description of the invention] do.

FIG. 1 is a drawing showing an embodiment of the present invention. In the figure, la and lb are document width regulating means which is a document table, and 2a and 2b are fixed to the document width regulating means la and lb. The sliding resistors 3a and 3b are connected to the sliding resistors 2a and 2b, and are A/D converters for digitizing the resistance values thereof.

A voltage is applied to the sliding resistors 2a, 2b, and when the document width regulating means 1a, lb is moved according to the width of the document, the output voltage of the sliding resistors 2a, 2b changes, and its value A/D conversion is performed by A/D converters 3a and 3b. A/
The digital signal after D conversion is sent to the image processing device 4, where the document width (both ends) can be detected based on the digital signal value.

Detection of the leading edge and trailing edge of a document is performed by providing a document detection sensor before the image reading section.

According to this embodiment, the width of the document is detected by adjusting the width of the document width regulating means to the width of the document, and the leading edge and trailing edge of the document are detected by the method described above to indicate the outer frame of the document. It can be seen that there is no information outside the outer periphery of the document, but by narrowing the width of the frame shown at this time, for example, the memory capacity can be reduced when saving the scanned image information in memory, and when printing. The amount of toner used also decreases.

FIG. 2 shows a second embodiment of the present invention, in which reference numerals 5a and 5b indicate racks attached to document tables 1a and lb;
6a and 6b are binions that engage with racks 5a and 5b; 7
a, 7b are binions 6a.

This is a rotary encoder that detects the rotation of 6b.

When the document tables 1a and 1b are moved to match the document width, the pinions 6a and 6b are rotated by the movement of the racks 5a and 5b. This rotation angle is detected by rotary encoders 7a and 7b, and the detected output is sent to the image processing device 4, and the document width is detected based on the detected output value.

Since the positions of the document plates 1a, lb cannot be detected when the rotary encoders 7a, 7bLJILE power is turned on, the document plates 1a, lb are moved to a predetermined reference position after the power source is turned on, for example, to the position where the document plates 1a, lb are opened to the maximum left and right. It is necessary to set it manually or automatically.

In this embodiment, the rotation of pinions 6a and 6b is controlled by an encoder? Since the encoders 7a and 7b are detected as digital signals, the mechanism is simple because the outputs of the encoders 7a and 7b can be input directly to the image processing device.

FIG. 3 shows a third embodiment of the present invention, and a fourth embodiment of the present invention is shown in FIG.
The figure is a side view thereof.

In the figure, 11 is a light bulb that is a light source, 12 is a lens for concentrating the light from the light bulb 11, 9 (9a, 9b) is a sensor that receives the light from the light bulb 11, and 8 (8a, 8b) is the first manuscript.
(la, lb), a wedge-shaped light shielding member that changes the amount of light received by the sensor 9 as the first document moves; 13, a slit that regulates the amount of light entering the sensor 9; 10a; , fob is an amplifier for amplifying the output of the sensor 9.

The light from the light bulb 11 is focused by the lens 12 and sent to the sensor 9.
However, when the light shielding member 8 is moved in accordance with the width of the document on the document table 1, the light shielding member 8 also moves in conjunction with the document table 1. As the light blocking member 8 moves, the amount of light incident on the sensor 9 changes. This amount of change is amplified by amplifiers 10a and 10b, digitized by A/D converters 3a and 3b, and input to the image processing device 4.

[Effects of the Invention] As described above, by providing the document width detecting means in the document width regulating member, the document width can be accurately detected in advance before reading the document image. This confirms that there is no document information outside the read range. Also,
This has the advantage that the memory capacity can be saved because the external part of the document can be deleted from the image information when the memory is manually loaded. Furthermore, by using the detected size of the document as a signal to specify the print area of the printer when printing,
You can obtain prints that are close to the original manuscript.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing a first embodiment of the present invention, Fig. 2 is a block diagram showing a second embodiment of the present invention, and Fig. 3 is a block diagram showing a third embodiment of the present invention. , FIG. 4 is a side view of FIG. 3. la, lb... document table, 3 a, 3 b...-A10 converter, 4... image processing device. Figure 1 Figure 2

Claims (1)

[Claims] 1) An image reading device with a moving document type, characterized in that the document width regulating device is provided with a document width detecting device for detecting the document width.