JPH0219877Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a barcode reader having a guide light for guiding the barcode reader to a predetermined reading position.

[Prior Art] In recent years, barcode readers that read barcodes that display numerical information have become widely used and are actively used, but there are considerable restrictions on the distance between the barcode and the reader, Barcode information cannot be read accurately unless the reader is placed inside the barcode. In fact, optical devices have been devised so that they can be used within a considerable range of distance, but the current situation is that users rely solely on their intuition as to the distance.

[Object of the invention] An object of the invention is to provide a barcode reader having a guide light that directs the optimum position of the barcode reader by irradiating the barcode with two types of guide light.

[Summary of the invention] The gist of the invention to achieve the above objectives is as follows:
In a barcode reader that optically scans a barcode with a scanning light beam and reads information on the barcode using the reflected light, two range display guide lights are used to display the barcode in order to indicate the effective range of the scanning light beam. a first projection means for projecting images from both sides of the reader toward an end of the barcode in a divergent manner; and two image forming display guide lights for indicating a proper imaging position of the scanning light beam. and second projection means for respectively projecting light from both sides of the barcode reader so as to intersect at the center position of the barcode at the appropriate imaging position. .

[Embodiments of the invention] The invention will be described in detail based on illustrated embodiments.

1 and 2 are cross-sectional views of the reading device. Here, 1 is a casing, 2 is a transparent protection plate facing the barcode, and 3 is a grip part that houses the battery.
A rotating polygon mirror 5 rotated by a motor 4 is arranged approximately in the center of the housing 1 . The rotating polygonal mirror 5 is formed of an optical block 6 made of transparent synthetic resin or the like, and on its upper surface, for example, four flat mirrors 7 are arranged symmetrically about a rotation axis 8. In reality, these flat mirrors 7 utilize total internal reflection by grinding the optical block 6 at an angle of 45 degrees with respect to the rotation axis 8. Further, a convex lens surface 9 is formed on the bottom surface of the optical block 6 below each flat mirror 7, and each flat mirror 7 and each convex lens 9 form a pair. A laser light emitting diode 10 is disposed below the end of the rotating polygon mirror 5, and the beam is made to enter the convex lens surface 9 of the optical block 6 and the flat mirror 7 via the collimator lens 11. Further, a Tory lens 12 is disposed inside and below the protection plate 2, and a light receiving element 13 is provided at a substantially focal position of the Tory lens 12 within the housing 1.

Furthermore, light emitting diodes 14a and 14b for guiding light are arranged at two locations inside the housing 1, and in front of these light emitting diodes 14a and 14b, imaging lenses 15a and 15b are arranged on both sides inside the protective plate 2. Mirrors 16a and 16b are arranged on both sides of the housing 1, respectively.

Therefore, the light beam emitted from the light emitting diode 10 enters the rotating polygon mirror 5 which is rotated at high speed by the motor 4 through one of the convex lenses 9, and is directed toward the protection plate 2 by the flat mirror 7. It is emitted,
Each flat mirror 7 is scanned by a predetermined angle. In this case, the collimator lens 11
The light beam from the light emitting diode 10 is made parallel and incident on the convex lens surface 9, and the focal length of the convex lens surface 9 determines the imaging position of the scanning beam.

In the light receiving element 13, the Torytsu lens 1
It is possible to receive the reflected light of the barcode information incident through 2 and convert it into numerical information.

The light beams that go straight from the light emitting diodes 14a and 14b for guide light to the imaging lenses 15a and 15b are converged by the imaging lenses 15a and 15b, respectively, and appear on the barcode B to be read as shown in FIGS. 1 and 3. The barcode is projected as a spot light, and the user is instructed to maintain the posture of the reading device so that the barcode B exists between the two projected points Sa and Sb. Also, light is emitted from the light emitting diodes 14a, 14b, and mirrors 16a, 1
The light beams reflected by 6b are respectively emitted from the sides toward the center, and are similarly emitted from the imaging lens 15.
a and 15b, and is imaged at the center of the barcode B as spot lights Sc and Sc'. The geometrical positional relationship is determined so that when the spot lights Sc and Sc' from both sides overlap on the barcode B, the optimum distance is reached.

In other words, the spot lights Sa and Sb are emitted so as to display the scanning angle θ by the rotating polygon mirror 5, and the spot lights Sc and Sc' are emitted toward the scanning center line at the imaging position of the scanning beam. .

Therefore, when the user operates this barcode reader toward barcode B,
If it is confirmed that barcode B is within the range of spot lights Sa and Sb projected on both sides of the barcode, barcode B can be read almost accurately.
To further ensure this distance, accurate reading can be achieved by providing a position on the barcode B where the spot lights Sc and Sc' directed toward the center intersect.

Note that the guide light is distinguished from the scanning beam from the rotating polygon mirror 5, and in order to avoid reading errors by the light receiving element 13, the guide light is set to a wavelength range different from that of the scanning beam, or a modulation frequency different from that of the scanning beam. It is desirable to do so.

[Effects of the invention] As explained above, the barcode reader with guide light according to the present invention can give instructions to the user about the position and orientation of the barcode reader with respect to the barcode using two types of guide lights. The user can use it without worrying about the spacing.

[Brief explanation of the drawing]

The drawings show an embodiment of a barcode reader having a guide light according to the present invention; FIG. 1 is a sectional view thereof, FIG. 2 is a sectional view thereof, and FIG. 3 is an explanatory diagram of a spot light on a barcode. 1 is a housing, 2 is a protection plate, 5 is a rotating polygon mirror,
6 is an optical block, 7 is a flat mirror, 9 is a convex lens surface, 10, 14a, 14b are light emitting diodes,
13 is a light receiving element, 15a and 15b are imaging lenses,
16a and 16b are mirrors.

Claims (1)

[Claims for Utility Model Registration] 1. In a barcode reader that optically scans a barcode with a scanning light beam and reads information on the barcode using reflected light, two a first projection means for projecting guide light for range display from both sides of the barcode reader toward an end of the barcode in a divergent manner; and second projection means for respectively projecting two image-forming display guide lights from both sides of the barcode reader so as to intersect at the center position of the barcode at the appropriate image-forming position. Barcode reader with guide light. 2. A barcode having a guide light according to claim 1, wherein the first and second projection means share a light emitting source and an imaging lens on each side of the barcode reader. leader. 3. Utility model registration claim 2, wherein the two image forming display guide lights guide the light flux from the light emitting light source to the image forming lens via a reflecting mirror provided on the inner surface of the bar code reader. A barcode reader having a guide light as described in Section 1.