JPS61164369A - Manual image scanner - Google Patents

Abstract

PURPOSE:To attain miniaturization and low cast by using a drive device so as to gate an image signal for main scanning at an interval proportional to a moving speed in moving an optical system thereby eliminating the need for a driving device such as a motor. CONSTITUTION:The rays of light from a light source 2 are irradiated on a paper sheet 1 on which an image such as a graph or a character to be read are written, the rays of light are received by a sensor 3 having photodetecting windows arranged in a line, the output of the sensor 3 is converted into a digital image signal 11 by a threshold value circuit 5 and a shaping circuit or the like, a turning angle detecting circuit 6 measures the amount of turning of a turning device 4 turned as an optical system moves and outputs a trigger signal 12 at every prescribed angle of turning. The trigger signal 12 generates a sampling gate signal 14 synchronizing with the period signal 10 of the main scanning, the image signal 11 is fetched only when the signal 14 is logic 1 so as to fetch the image 15 on the paper at a prescribed interval.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an image scanner device for optically reading figures, sentences, etc. written on paper and inputting the images into a computer.

(Prior art) In conventional devices that read images such as figures and characters written on paper, the main scanning is self-scanning of a sensor such as a COD or contact type sensor, and the sub-scanning is a drive of the paper or optical system. Images were captured by moving it at a constant speed using a mechanism. However, in order to move the paper or the optical system at a constant speed.

Since a motor, a drive circuit, and other mechanisms are required, the image scanner device is bulky, expensive, and difficult to use as a means for simply inputting images.

(Objective of the Invention) An object of the present invention is to provide a small and inexpensive image scanner device that does not require a drive mechanism such as a motor.

(Means for Solving the Problems) The image scanner device of the present invention performs main scanning for image reading using a sensor, and performs sub-scanning by manually moving the optical system on the paper surface, thereby eliminating variations in movement speed. It is configured to include a rotation mechanism that rotates according to the movement of the optical system for correction, and a circuit that converts the amount of rotation of the rotation mechanism into a signal.

Note that when moving the optical system manually, the sub-scanning speed is not constant; however, by capturing the main scanning signal every time the optical system moves a certain distance according to the rotation amount signal of the circuit, the sub-scanning speed can be adjusted. Images can be input faithfully to the directional dimensions.

(Example) Hereinafter, the present invention will be explained with reference to the drawings.

FIG. 1 is a block diagram of this embodiment. 1 is a diagram.

It is a sheet of paper on which characters and other images to be read are written. The optical system is configured such that light is emitted from a light source 2Vc and one reflected light is received by a sensor 3 having light receiving windows arranged in a row. An example of an optical system including such a sensor is (
b) Using a long slender halogen lamp or fluorescent lamp as a light source,
A type of image sensor in which the reflected light is focused by a lens and received by a self-scanning scanner such as a COD, and (b) a form of contact image sensor in which a light source and a light receiving element are integrated and placed very close to each other on a sheet of paper. There are things, etc. In the latter case (b), the dot spacing of the image is equal to the spacing of the light receiving windows.

This contact type image sensor is also a type of self-scanning type that can sequentially take out images by applying a driving clock from the outside. The main scanning of the image is performed by the self-scanning sensor itself, and the time required for one main scanning is often several hundred microseconds to several milliseconds.

Referring again to FIG. 1, the output from the sensor 3 is converted into a digital image signal 11 by a threshold circuit 5, a shaping circuit, and the like. Reference numeral 4 denotes a rotation mechanism that rotates as the optical system moves.The amount of rotation is measured by a rotation angle detection circuit 6, and a trigger signal 12 is output every time the optical system rotates by a certain angle.

FIG. 2 shows a time chart in which only the required number of main scanning image signals are selected by a trigger signal so that a predetermined dot density is achieved in the sub-scanning direction. In the figure, 10 is a signal indicating the period of main scanning, and 11 is the image signal described in FIG. 1. 12 is the trigger signal described in FIG. 1, and via 13 it is possible to generate the sampling gate signal 14 synchronized with the main scanning periodic signal 1o. By capturing the image signal 11 only when the sampling gate signal 14 is logic 1, images can be captured at constant distance intervals on the paper as shown at 15. The main scanning period of the senna is generally from several 100 microseconds to several m5ec depending on the number of dots and the clock frequency. On the other hand, when the dot density is 8 lines/I11,
The trigger signal generates a pulse every time the optical system moves 0.125 degrees.

If the moving speed of the optical system is about 1 cIIL to 3 (In) per second, in the above example, the speed is about 12.5 m5 ec to 4 m5 ec.
Generates a trigger pulse at a certain level. Therefore, the main scanning period is 2
In the case of m5ec, if an image is captured approximately 6 to 2 times in the main scan and once in Vc, an image can be captured at a dot density of 8 dots/volt.

(Effects of the Invention) As explained above, the present invention gates the main scanning image signal at an interval proportional to the moving speed using a rotating mechanism when moving an optical system, thereby controlling a driving mechanism such as a motor. This has the effect of realizing a compact and inexpensive image scanner device.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a diagram showing the tie lhf yard when the image signal shown in FIG. Yes. 1...Paper, 2...Light source, 3...
Sensor, 4... Rotation mechanism, 5... Threshold circuit, 6... Rotation angle detection circuit, 11...
・Image signal, 12...Trigger signal.

Claims (1)

[Claims] An optical system that inputs an image for one row by receiving reflected light through a row of light-receiving windows, a rotation mechanism that rotates as the optical system moves on the paper surface, and a signal indicating the amount of rotation of the rotation mechanism. A manual image scanner characterized in that it has a circuit.