JPH04217081A - Embossed image reader - Google Patents

Abstract

PURPOSE:To surely extract and read the embossed image formed on a recording medium even if some shift is generated in a geometrical position relation of the recording medium, a light source and an image sensor owing to distortion and deformation of the recording medium. CONSTITUTION:A slit Light is projected to a display of a card (recording medium) on which embossing is formed, a range containing a slit light projection area on the surface of the card is photographed by an area sensor, a slit light projection pattern contained in its image data is extracted, and also, the slit light projection pattern extracted in connection with carrying of the card is stored as time series data.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an embossed image reading device for reading embossed images formed on a recording medium such as a card.

0002

2. Description of the Related Art Conventionally, imprint devices have been used in ATMs, CDs, and the like to print an embossed image formed on a card used in a transaction on a processing slip during transaction processing.

[0003] Conventional imprint devices include a method in which a copy type slip is placed on a card and an embossed image is transferred onto the slip by pressing the copy slip against the card using a roller or the like with a constant pressure. There was a method in which the surface of the card was captured as an image and printed out on an image printer.

[0004] In the former method, ink may adhere to the embossments of the card due to poor conveyance of the photocopy slip, resulting in the card being stained. In the latter method, the entire device is miniaturized and the mechanical transport system is simplified, so reliability is improved and read data can be converted into electronic information.

As a method of reading an embossed image using an image sensor, illumination light is irradiated onto the recording medium from an oblique direction, a specular reflection image from the recording medium is captured by the image sensor, and the recording is determined based on the output signal level of the image sensor. The applicant has proposed an embossed image reading device for reading embossed images formed on a medium in Japanese Patent Application No. 2-7
No. 4345 was filed earlier.

FIGS. 6 to 8 show the configuration of an optical system of a conventional embossed image reading device. Projecting slit light from a slit light source onto a card with an embossed shape as shown in Figure 6,
The CCD line sensor is configured to image the projected portion. However, in the figure, the imaging optical system for the line sensor is omitted for clarity. In this way, the line sensor is configured to image the projected portion of the slit light, and as shown in FIG. By predetermining the positional relationship between the light source, the line sensor, and the card so that no light is received, the embossed image can be read from changes in the output signal level of the line sensor as the card is transported.

[0007]

However, in the conventional embossed image reading device that changes the amount of light received by the line sensor depending on the height of the reflective surface of the projected slit light,
The geometric positional relationship between the light source and the line sensor changes due to shakes and vibrations of the surface of the recording medium such as a card while the recording medium is being conveyed. For example, as shown in FIG. 8, if the card moves a little away from the light source and the line sensor, the line sensor will receive substantially the same amount of light reflected from the card surface and the top of the emboss. As a result, the amount of light received changes less depending on the presence or absence of embossing, making it difficult to reliably extract the embossing.

An object of the present invention is to provide an embossed image reading device that can reliably read an embossed image even if there is some deviation in the positional relationship of the recording medium with respect to the light source and the image sensor.

[0009]

[Means for Solving the Problems] An embossed image reading device of the present invention includes means for projecting slit light at a constant angle of incidence from an oblique direction onto a recording medium on which an emboss is formed, and an area sensor for imaging the recording medium. and means for converting the output signal of the area sensor into digital image data,
The present invention is characterized by comprising means for extracting a slit light projection pattern from the image data, and means for storing the slit light projection pattern as time series data as the recording medium is conveyed relative to the slit light projection means.

0010

[Operation] In the embossed image reading device of the present invention, a slit light is projected from an oblique direction at a constant angle of incidence onto a recording medium on which an emboss is formed, and the recording medium on which the slit light is projected is imaged by an area sensor. Ru. The output signal of the area sensor is converted to digital image data,
A slit light projection pattern is extracted from the image data. As the recording medium is conveyed relative to the slit light projection means, the slit light projection patterns are sequentially stored as next series data.

Even if a slight deviation occurs in the geometrical positional relationship between the slit light projection means, the area sensor, and the recording medium due to the above-described effects, the area sensor can cover a relatively wide area including the slit light projection area on the surface of the recording medium. Since images are always captured, it is possible to reliably extract and read the embossed image.

0012

[Embodiment] In the following explanation, a card reader/slip issuing machine in an ATM will be taken as an example.

FIG. 2 is a block diagram of the card reader/slip issuing machine. In the figure, a CPU 10 is one of the slave CPUs in the control unit constituting the ATM, and performs processing of reading a card, reading an embossed image provided on the card, and issuing a slip showing an imprint along with transaction details. ROM11 is a memory in which a program to be executed by the CPU 10 is written in advance, and RAM12
is a memory used as various working areas such as temporary storage of card data, temporary storage of processing contents to be printed on slips, and temporary storage of embossed images. CPU1
In addition to this, various circuits described below are connected to the bus No. 0.

The image imprint control circuit 13 mainly controls the reading of the embossed image provided on the card, and receives timing signals from the motor control circuit 19, as well as the slit light source 14, area sensor 15, and A.
A timing signal is provided to the /D converter 17, data processing circuit 18, etc., respectively. The area sensor 15 is, for example, a CCD area sensor, and receives light (accumulates charge) and outputs a video signal in accordance with a timing signal given from the image imprint control circuit 13. The amplifier circuit 16 amplifies the signal, and the A/D converter 17 sequentially samples and holds the signal and converts it into one or several bits of digital data. The data processing circuit 18 temporarily stores data for one line or one pixel, and outputs a request to the CPU 10 to read the temporarily stored data. Upon receiving this read request, the CPU 10 reads the data in the data processing circuit 18, performs processing to be described later, and then stores it in a predetermined area of the RAM 12.

The motor 20 is a pulse motor for receiving/ejecting and transporting cards, and is controlled by a motor control circuit 19 and provides its timing signal to the image imprint control circuit 13. The printer 22 prints the embossed image on the slip along with the details of the transaction. The interface circuit 21 performs the print control interface. The card reader 24 reads the contents recorded on the magnetic stripe of the card being transported.
The interface circuit 23 performs the reading control interface.

Next, FIG. 1 shows the configuration of the optical system of the embossed image reading device. In FIG. 1, the slit light source projects slit light onto the card surface from an oblique direction at a constant angle of incidence.

The lens system images a certain area of the card surface onto the light receiving surface of the area sensor. The area sensor outputs the image as a video signal.

Next, the processing procedure of the CPU shown in FIG. 2 is shown in FIG. 3 as a flowchart. Further, FIG. 4 shows an example of the imaging range of the area sensor, and FIG. 5 shows an example of time series data of the obtained embossed image. The processing procedure of the CPU will be explained below based on FIGS. 3 to 5. As shown in FIG. 4, the area sensor images a certain width range centered on the position where the slit light is projected on the card surface. In this example, b is a slit light pattern projected onto the embossed portion, and a and c are slit light patterns projected onto the ground surface of the card. In step n1 shown in FIG. 3, a plurality of line segments a, b, and c are extracted from the image data. Subsequently, in step n2, as shown by I in FIG. 4, a virtual line is calculated that connects the long line portions of the extracted line segments in a straight line. Subsequently, in step n3, line portions b that do not belong to the virtual line among the plurality of already extracted line segments are extracted as embossed images. Then, in step n4, the extracted embossed images are sequentially stored in sequence according to the position of the card. FIG. 5 shows an example of embossed images extracted and sequentially stored in chronological order. The above-described process is sequentially and repeatedly executed for each unit transport of the card, and the process ends when the card is transported a predetermined distance (n5).

With the above configuration, even if the distance of the card to the slit light source and the area sensor changes, the position of the line segment of the slit light projection pattern in the image data will only shift overall. As long as the slit light projection pattern exists in the image data, the embossed image can be reliably extracted and read.

[0020]

According to the present invention, an image of an emboss formed on a recording medium can be extracted even if there is some deviation in the geometrical positional relationship between the recording medium, the slit light projection means, and the area sensor. I can do it. Therefore, the embossed image can be reliably read even when the embossed image is read while a somewhat deformed card or the like is being transported by a transporting mechanism having a relatively simple guide means.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an optical system of an embossed image reading device according to an embodiment, FIG. 2 is a block diagram of a control section of a card reader/slip issuing machine according to an embodiment, and FIG. 3 is a flowchart showing its processing procedure. FIG. 4 is a diagram showing an image of the imaging range of the area sensor in the example, and FIG. 5 is a diagram showing an example of time-series data of the obtained embossed image. 6 to 8 are diagrams showing the configuration of an optical system of a conventional embossed image reading device.

Claims (1)

[Claims] 1. Means for projecting slit light at a constant angle of incidence from an oblique direction onto a recording medium on which an emboss is formed; an area sensor for capturing an image of the recording medium; and converting an output signal of the area sensor into digital image data. An embossed image reading system comprising means for converting, means for extracting a slit light projection pattern from the image data, and means for storing the slit light projection pattern as time series data as the recording medium is conveyed relative to the slit light projection means. Device.