JPS5968081A - Optical character reader - Google Patents

Abstract

PURPOSE:To prevent regular reflection from a body to be read and to read character information written on the body to be read securely by providing a light-diffusing semitransparent member on a read surface side. CONSTITUTION:A semitransparent glass plate 7 as a light-diffusing semitransparent member is arranged on the surface side of windowed postal matter P. Light from a fluorescent lamp 3 illuminates the surface of the postal matter P through the glass plate 7 and its reflected light forms an image on an image sensor 5 through the glass plate 7 and an image formation lens 4. Therefore, even if cellophane paper provided on the address information area 1 of the postal matter P wrinkles, regularly reflected light from the cellophane paper is prevented by the glass plate 7 from making incident to the sensor 5. Consequently, a postal number 2 in the address information area 1 covered with the cellophane paper is read securely. Thus, the character information written on the body to be read is read securely.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an optical character reading device that optically reads a postal code written on, for example, a so-called windowed mail piece.

[Technical background of the invention]

Generally, in a so-called windowed mail item, a frame-shaped destination information area 1 is covered with glossy cellophane paper, as shown in FIG. When reading the postal code 2 in the destination information area 1 from such a windowed mail P, an optical character reading device as shown in FIG. 2 has conventionally been used. That is, arrow a
The surface of the mail P being conveyed in the direction is illuminated with a fluorescent lamp 3 as a light source, and the reflected light is imaged by an imaging lens 4 and onto an image sensor 5 as a photoelectric converter and converted into an electrical signal. , and sends the output signal to the signal processing circuit 6 for predetermined signal processing.

[Problems with background technology]

However, the conventional device described above has the following problems. That is, even if different sides of the mail P are illuminated with diffused light from the fluorescent lamp 3 or the like, the cellophane paper in the destination information area 1 may have wrinkles or the like, and specularly reflected light from the cellophane paper will enter the image sensor 5. . As a result, as shown in FIG. 3, the character signal S1 is included in the output signal of the image sensor 5.
+S! *A specular reflection light signal N appears in the white direction with respect to Sm. This specular reflection light signal N is the character signal Sl
, S, , S3, the character signal will disappear. FIG. 3 shows a case where the specular reflection source signal N corresponds to the character signal S3. Note that in FIG. 3, G is a background signal portion, and B is a blanking signal. In this way, when the specular reflection light signal N appears in the output signal of the image sensor 5,
The necessary character signal disappears, making it impossible to reliably read the postal code 2.

[Purpose of the invention]

The present invention has been made in view of the above circumstances, and its purpose is to prevent specular reflection from the object to be read and to reliably read character information written on the object to be read. The objective is to provide an optical character reading device that can.

[Summary of the invention]

The present invention prevents specular reflection from above the object by installing a light-diffusing semi-transparent member (for example, a glass plate) on the side of the object to be read. 0 [Embodiment of the Invention] An embodiment of the present invention will be described below with reference to the drawings. Note that the same parts as in FIGS. 1 to 3 are designated by the same reference numerals, and their explanations will be omitted. As shown in FIG. 4, a translucent member such as a translucent glass plate 7 is installed on the front side of the mail P, and the surface of the mail P is pressed against the glass plate 7 to transport the mail P. It has become. The glass plate 7 is semi-transparent with a light transmittance of about 70 inches, and has light diffusing properties. The light from the fluorescent lamp 3 is irradiated onto the surface of the mail P via the glass plate 7, and the reflected light is guided to the imaging lens 4 via the glass plate 7 and is imaged on the image sensor 5. Ru.

With such a configuration, address information area 1 on mail P
Even if the cellophane paper provided on the screen is wrinkled, the specularly reflected light from the cellophane paper will be diffused by the glass plate 79, and the specularly reflected light from the cellophane paper will not directly enter the image sensor 5. It can be prevented. As a result, the fifth
As shown in the figure, the specular reflection source signal N does not appear in the output signal of the image sensor 5, so the character signal S! ,S,,S
3 does not disappear. This makes it possible to reliably read the postal code 2 within the destination information area 1 covered with cellophane paper.

In the above embodiment, a case has been described in which a postal code written on a windowed postal item is read, but the present invention is not limited to this. For example, when reading the entire address information including a postal code, In short, it can be applied to any device that optically reads character information written on an object to be read.

〔Effect of the invention〕

As detailed above, the present invention provides an optical character reading device that can prevent specular reflection from the object to be read and reliably read character information written on the object to be read. can.

[Brief explanation of drawings]

Fig. 1 is a plan view showing an example of a mail item with a window, Fig. 5-2 is a block diagram schematically showing a conventional optical character reading device, and Fig. 3 is a waveform of a read signal by the device shown in Fig. 2. Figure, 4th
The figure is a schematic configuration diagram showing one embodiment of the present invention, and FIG. 5 is a waveform diagram of a read signal in the same embodiment. P... Mail, 1... Destination information area, 2... Postal code, 3... Fluorescent lamp, 4... Imaging lens, 5...
Image sensor, 6... Signal processing circuit, 7... Translucent glass plate. Applicant's agent Patent attorney Takehiko Suzue 61 Figure 1 to 1 Figure 2 Figure 1 to 4 Figure 3 Figure 1 to 4 Figure 5 --467=

Claims (1)

[Claims] In an optical character reading device that optically reads character information written on an object to be read, a light-diffusing semi-transparent member installed on the surface to be read of the object and a translucent an optical type comprising: a light source that irradiates light onto the surface of an object to be read; and a photoelectric converter that receives light reflected by the light source from the surface of the object through the semi-transparent member. Character reading device.