JPS60158A - Picture input device - Google Patents

Abstract

PURPOSE:To assure the collection of the picture data by providing a means which displays the state of a picture detecting function and therefore detecting the scan carried out to the next line before the transfer of data is through. CONSTITUTION:The LED23 serving as light sources are arrayed in the lengthwise direction of a reading head 1 of a picture input device, and the light given from the LED23 is exposed to an original 20 through a supporter 2 of a light transmitting material. The reflected light sent from the original 20 is made incident to an image formation element array 22. Then the signal output corrsponding to the incident light is formed into images on the photodetecting surface of a sensor 21. An alarming LED8 is provided on the upper surface of the head 1 to display the state of a picture detecting function. Then the scan time is compared with the transfer time to detect the scan carried out to the next line before the transfer of data is completely through. This fact is displayed to the LED8 and the collection of a picture data is assured.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a digital image input device for copying machines, facsimile machines, 11-child files, etc., and particularly to a small-sized, manual type image input device.

A close-contact line sensor has been proposed in which an optical sensor array in one-to-one correspondence with a document or a document is brought into close contact with the document to read the image.

Using this contact line sensor eliminates the need to secure space for a conventional optical system, and is particularly effective in reducing the weight and size of the device.

This invention! The present invention provides a so-called hand scanner type image input device that takes advantage of the compactness of a one-line sensor and manually scans an IQ document and reads image information.

FIG. 1 shows a schematic diagram of an image reading device according to the present invention.

A reading head section 1 housing a contact line sensor is reciprocally coupled to a support body 2 having a sliding mechanism 3, and can be opened and closed as a unit with respect to a document table 6 by an opening/closing coupling section 7.

The original to be read is placed on a support 2 made of transparent material such as glass.
The image is inserted upward between the document platen 6 and the image area 5, and is read out line by line in the longitudinal direction of the head in synchronization with manual scanning in the range surrounded by the image area 5. 8 is a warning LET
).

FIG. 2 shows the cross-sectional structure of the reading head 1. Light from LF3Ds 23 arranged in the longitudinal direction of the head passes through a transparent material (glass) support 2 and exposes the original 20. The reflected light from the original 20 is imaged by a short focus imaging element array (hereinafter referred to as an imaging array) 22 on the light receiving surface of a sensor 21 which outputs a signal according to the incident light.

The detection surface (light receiving surface) of the reading head 1 is shown outside of FIG.

As shown in the figure, LEs arranged in an array for reading original images
In addition to D23, it has an integral LED 30 for detecting the scanning position. LED3Q for scanning position detection and this LED3
In the figure, an imaging array 61 for forming an image of the light reflected from the support 2 is located at a position opposite to the position reading slit 4 printed outside the image area of the support 2, and a light-receiving element for reading the image R. established in In this example, the pitch of 20+11111 light receiving elements in the longitudinal direction of the head length is 62.5.
It has a resolution of μ (16 pel) (5120 images per line), and therefore, for preferable image reproduction, it is necessary to detect the position of the reading head 1 at a pitch of 62.5 μ in the scanning direction. Slit width approximately 30μm Duty ratio 50
% slit 4, the light-receiving surface of the light-receiving element for position detection was set to 40μ" It is possible to transfer 5120 pixel image data and accumulate photocurrent, making it possible to record data reliably.Also, since the position of the reading head 1 is optically detected, the position can be detected in the same process as forming the image sensor section. It is possible to realize a light receiving section and a light source for detection, which is very convenient for production.

Next, FIG. 4 is a diagram showing the circuit configuration of the control section, and the operation will be explained using this diagram.

In the figure, a part 40 surrounded by a broken line is a sensor part,
5120 photodiodes 43 detecting one pixel each
The detected current is extracted as serial data by sequentially connecting 5120 switches SW42 connected to each other by the shift output of the shift register 41 driven in synchronization with the output of the reference oscillator 49.

The detection current reaches the signal level ■ in the amplifier 44 as an image analog signal.

On the other hand, the operation start timing of the shift register 41 is determined by the slit end detection signal obtained by amplifying and waveform shaping the output of the light receiving element 47 for scanning position detection by the gate 48.

FIG. 5 shows the signal waveforms at the above and 02 points.

Generally, since the operation is performed manually, the signal read from the slits 4 arranged at equal intervals is generated at an irregular period as shown in Fig. 2, but the rising edge of the signal starts the operation of the counting circuit 50. The counting circuit 50 counts clock pulses from the reference oscillator 49 from the rising edge of the slit end detection signal (2), and inputs a control signal indicated by O to the shift register 41 for the time required to read one line. SW42 is sequentially connected in synchronization with the clock pulse output from the reference oscillator 49 only during the ``H'' level period of this control signal O, and one line of image data is serially outputted with the waveform shown in (2).

In Fig. 4, the image analog signal ■ is the A/D conversion circuit 4.
5, the data is converted into a digital value of a predetermined bit, and further binarized by a predetermined image signal processing circuit 46, and then input as video data to an image memory 52 having a storage capacity of, for example, one original document.

On the other hand, the memory drive circuit 51 sequentially determines the addresses of the image memory 52 by inputting the pulse output from the reference oscillator 49 and the slit end detection signal as the main scanning clock and sub-scanning clock.

By the way, if manual scanning is performed at high speed and the reading head 1 reaches the reading position of the next line before the transfer of one line of image data is completed, data recording becomes impossible. Therefore, in such a case, the unreadable state is displayed to the operator. In FIG. 4, numeral 54 is a control circuit that detects the scanning speed of the reading head 1 and turns on the display LED to issue a green notice when transfer for one line cannot be secured. Details will be explained with reference to FIGS. 6 and 7.

The image data transfer timing is determined by inputting the scanning position detection signal to the J input of the 7-rip 70-tube (F/F) 541 to the J- terminal, that is, the rising edge of the slit end detection signal 50. Transfer signal ■ is output from. The time t is caused by the gate circuit delay. As shown in the 4th line in the figure, when performing high-speed scanning, the data transfer for the previous line (lowth line) has not yet been completed, so the input terminal of the FF 541 remains at 'H' level. Therefore, the output ■ of the FF 541 is inverted at this time.

This change is latched by the 几S flip-flop (FF) 542 and the warning LED 13 is turned on. Note that the lighting signal is also input to the memory drive circuit 51 to stop the address counter and prohibit writing of the image signal. This warning state is reset by turning on switch 5W543.

As mentioned above, by comparing the scanning time and the transfer time in a device that transfers and records manually scanned image signals line by line, it is possible to detect whether scanning to the next line was performed before the transfer was completely completed. If detected, an LED 8 on the upper surface of the scanner section 1 warns the operator of the detection, thereby making it possible for the operator to recognize that image data has been recorded more reliably.

As explained above, since the status of the image detection function is displayed to the user, reliable image input can be achieved.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram 1 and 2 of an image reading device according to the present invention.
3 is a diagram showing the detection surface of the reading head, FIG. 4 is a diagram showing the circuit configuration of the control section, FIGS. 5 and 7 are waveform diagrams, and FIG. FIG. 6 is a block diagram of the warning control circuit, in which 1 is a reading head, 2 is a transparent material support, 4 is a slit, 8 is a warning LED, 21 is a sensor, and 25 is an LED. Applicant Canon Co., Ltd. Figure B

Claims (1)

[Claims] An image input device having a manual scanning mechanism. An image input device characterized by comprising means for displaying a state of an image detection function.