JP2007058298A - Device for reading image and code - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device for reading images and codes that enables accurate subject positioning without focusing on the subject. <P>SOLUTION: An imaging device 1, an illuminator 2 and an imaging switch 4 are fixedly arranged in a support casing 3 with a subject observation window to form an integral structure. As an auxiliary, a guide (window frame) 7 is provided for positioning a subject in the center position in the casing bottom. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a small “image and code reading device”.

  It is well known that small-sized “image and code reading devices” represented by bar code readers and QR code readers have been widely used for industrial and consumer purposes. Many of these products, which are portable, are provided with a mechanism that enables a reading operation regardless of distance within a certain range in order to expand the application range. Further, for miniaturization, no special function for aligning images and codes is provided.

The characteristics of the conventional products as described above have caused the following operational problems.
That is, in the conventional “image and code reading device”, a mechanism for fixing the distance between a subject (barcode or QR code) and an imaging device (such as a CCD camera or a CMOS camera) is “an image and code reading device”. Therefore, when the subject is imaged, it is necessary for the human being and / or the imaging apparatus to focus on the subject. In addition, the subject positioning needs to be performed roughly without a monitor, or it is necessary for a human to watch the image while the image captured by the imaging device is displayed on the monitor screen. These have caused the complexity and inefficiency of code reading.

  It is an object of the present invention to provide an “image and code reading device” that does not require subject focusing and enables accurate subject positioning, thereby making code reading simple and efficient. Yes.

In order to solve the problems of the conventional products described above, the “image and code reading device” of the present invention has been devised in several ways as summarized below. (1) The imaging device, the illumination, and the subject observation window are integrated, and the distance between the subject and the imaging device is kept constant. (2) A part of the integral structure is made transparent or translucent. (3) A part of the integral structure is made of a material that reflects light of a specific wavelength. (4) An object positioning observation window is provided on the bottom surface of the integrated structure. (5) An illumination light shielding plate and an illumination light scattering plate are provided inside the integrated structure.

With these devices, an “image and code reading device” that does not require focusing of the subject and can easily place the subject at the center of the imaging is realized. The effects of the invention obtained from the above device are as follows. (1) Since the distance between the subject and the imaging device is kept constant, there is no need to adjust the focal length when reading an image and code. (2) Since a part of the integral structure is transparent or translucent, the image and the code can be aligned when viewed from the outside of the structure, so that the alignment can be performed easily and quickly. (3) Since a part of the integrated structure reflects light of a specific wavelength, strong light from outside hardly causes halation even in the reading apparatus. (4) The subject can be easily arranged at the imaging center position by the subject positioning observation window provided on the bottom surface of the integrated structure. (5) The illumination light shielding plate or illumination light scattering plate can uniformly illuminate the subject, and the return light from the subject can be reduced.

  An embodiment of the invention will be described based on an example with reference to the drawings.

In FIG. 1, the imaging device 1, the illumination 2, and the imaging switch 4 are all arranged and fixed centrally on the upper part of the support housing 3 with the subject observation window, and have an integral structure. The power supply and information collection cable 6 connects the imaging device 1, the illumination 2, the imaging switch 4 and a CPU (not shown) via a support housing 3 with a subject observation window.
In the embodiment, the power supply and information collecting cable 6 is a USB cable. 2 is a subject 5 to be read by the “image and code reading device” of the present invention, and in the embodiment, is a QR code on a plane.

  An operation for reading the subject 5 will be described. The subject 5 is placed on the bottom surface of the support housing 3 with the subject observation window. Specifically, a human first looks into the subject 5 through the support housing 3 with the subject observation window, and the center of the subject 5 and the center of the “guide (window frame) 7 for positioning the subject at the center position of the bottom surface of the housing”. An “image and code reading device” is placed at the center on the QR code placement plane so that they are almost the same. The distance between the bottom surface of the support housing 3 with the object observation window and the imaging device 1 is designed so as to coincide with the focal length of the imaging device 1, so that it is automatically best only by a simple operation of “placement”. The subject 5 can be arranged at the shooting position. When a human determines that there is no blur or vibration, the human presses the imaging switch 4 so that the imaging device 1 captures an image of the subject 5 and transmits the image data to a CPU such as a personal computer. In the embodiment, the imaging switch 4 is a switch that is turned on only by a human being and turned off when released.

In the embodiment, the illumination 2 is always turned on to provide optimum shooting conditions.
In order to prevent direct light from the illumination 2 from directly entering the imaging device 1, a simple light shielding plate (not shown) is provided for the imaging device 1 and the illumination 2, and the light from the illumination 2 uniformly strikes the subject 5. Thus, a simple light scattering plate (not shown) for directly scattering light is provided in the vicinity of the illumination 2.

  Experimental data demonstrating the effect of the invention was collected by an actual machine based on such an example. As the subject 5, a black QR code (size: 9 mm square to 25 mm square) printed on a light-colored paper surface having various glossinesses was used. As a result, it was possible to capture a clear contrast in the indoor environment regardless of the size of the QR code and the state of the printing surface. The success rate of QR code reading determined by sending to a personal computer was 95% or more. However, when used in an outdoor environment, the contrast is lowered because the natural light intensity may be superior to that of the internal LED illumination, thereby reducing the reading success rate. In order to improve this, the cylindrical object observation window is made small in size, or the object observation window is made semitransparent based on blue to prevent light of a specific wavelength from entering inside. As a result, the same characteristics as the room were obtained.

  The success rate of QR code incorporation in a state where natural light was completely blocked was 99%. The blocking of natural light can be easily realized by eliminating the observation window from the support case 3 with the subject observation window and making the entire case opaque. If a “reader housing frame placement guide mark (not shown)” is placed on the printing surface of the subject 5 to place the subject in the center of the case, images and codes can be read without any problems in execution. It is. That is, when the above guide marks can be secured, the housing may be opaque.

  The “image and code reading device” of the present invention can be used for a QR code reader or a barcode reader.

FIG. 2 is an image and code reading device (longitudinal sectional view). It is an image and code reading device (bottom sectional view as seen from above). It is an image and code reader (top view).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Imaging device 2 Illumination 3 Support housing | casing with subject observation window 4 Imaging switch 5 Subject 6 Power supply and information collection cable 7 Guide (window frame) which arrange | positions subject to the center part of housing | casing bottom

Claims (7)

The imaging device 1 and the illumination 2 are fixed to a support housing 3 with a subject observation window, have an integral structure, and have a structure that can maintain a constant distance between the imaging device 1 and the subject. Code reader ". The “image and code reading device” according to claim 1, wherein all or part of the support housing with the object observation window is transparent or translucent. 2. The “image and code reading device” according to claim 1, wherein all or part of the support housing with the object observation window is made of a material that reflects light of a specific wavelength. 2. The “image and code reading device” according to claim 1, wherein a guide 7 is provided on a bottom surface of the support housing 3 with a subject observation window to place the subject at a central portion of the bottom surface of the housing. The “image and code reading device” according to claim 1, further comprising a light shielding plate inside the support housing 3 with one subject observation window. The “image and code reading device” according to claim 1, further comprising a light scattering plate inside the support housing 3 with one subject observation window. The imaging device 1, the illumination 2, and the support housing, characterized in that the imaging device 1 has a mechanism for maintaining a constant distance between the subject having the “reader housing frame layout guide mark” on the same plane and the imaging device 1. An “image and code reading device” in which the body has an integral structure.

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