JP3099246B2 - Document reading device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a document reading apparatus such as a facsimile or a printer.

[0002]

2. Description of the Related Art Conventionally, an original reading apparatus is mounted on a facsimile, a printer, or the like, and with the downsizing of these apparatuses, a reduction in the size of the original reading apparatus is required.

A conventional document reading apparatus will be described below.

FIG. 4 shows a configuration diagram of a conventional document reading apparatus, wherein (1) is a plan view seen from above, (2) is a side view of (1),
(3) is a front view of (1). FIG. 5 is a perspective view of FIG.
In both figures, 1 is a document having a width L, 1a is a reading line in the main scanning direction on the document 1, 2 is a reading window provided on a conveying surface of the document 1, and 3 is an optical signal of the reading line 1a. A line image sensor 4 for conversion, a lens 4 for forming an image of the read line 1a on the line image sensor 3, and a line light source 6 for illuminating the read line 1a having a length L. The reading line 1a is arranged to illuminate the reading line 1a while avoiding the reading optical path by the lens 3 and the lens 4, and its length must be equal to or longer than the reading length.

In the above configuration, when the reading line 1a having a length L is illuminated from the reading window 2 by the linear light source 6, the information on the original 1 is imaged on the line image sensor 3 via the lens 4 to form a line image. The signal is converted into an electric signal by the sensor 3.

[0006]

In such a conventional document reading apparatus, a linear light source 6 having at least the same length as the reading line 1a is required, which limits the miniaturization of the apparatus.

An object of the present invention is to solve the above-mentioned problem of miniaturization, and it is an object of the present invention to provide a document reading apparatus which is particularly advantageous when it is carried.

[0008]

According to the present invention, there is provided an original reading apparatus for intermittently conveying an original in a sub-scanning direction and reading a reading line in a main scanning direction by a line image sensor. At least two or more linear light sources are arranged in parallel to the reading line, and when reading a document, the linear light source illuminates the reading lines from different angles with respect to the document surface, and when not reading, the linear light source It is characterized in that it is reduced to one illumination range of the light source.

[0009]

According to the present invention, it is possible to secure illumination for at least the reading length when reading a document, and to reduce the width of the entire apparatus to a reading length or less when not reading.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a diagram showing a configuration of a document reading apparatus according to an embodiment of the present invention, wherein (1) is a plan view seen from above, and (2)
Is a side view of (1), and (3) is a front view of (1). FIG. 2 shows FIG.
It is a perspective view of. The original 1, the reading line 1a, the reading window 2, the line image sensor 3, the lens 4 and the like are the same as those in the conventional example, and thus the same numbers are given and the description is omitted.

Reference numerals 5a and 5b denote linear light sources for illuminating the original surface. The linear light sources 5a and 5b are arranged so as to illuminate the reading lines while avoiding the optical path for reading by the line image sensor 3. 5b illuminates the reading line 1a in the main scanning direction from the different A and B directions with respect to the original surface.

The operation of the document reading apparatus configured as described above will be described below.

At the time of reading a document, as shown in the perspective view of FIG. 2, two linear light sources 5a and 5b are arranged so that their illumination ranges hardly overlap each other.
A half of the read line 1a is illuminated by a, and the other half of the read line 1a is illuminated by the other linear light source 5b to secure an illumination range for the required length L of the read line.

Next, at the time of non-reading, as shown in the perspective view of FIG. 3, the respective linear light sources 5a and 5b are slid so that the illumination ranges of the two linear light sources are the same. At this time, the overall width of the apparatus is approximately L / 2.

Although the above embodiment has been described with reference to the case where two linear light sources are provided, two or more linear light sources may be provided if necessary.

The slide mechanism of the linear light source may be a means for sliding on a guide rail.

[0017]

As described above, the original reading apparatus according to the present invention can secure a light source width necessary for illuminating the original width when reading the original, and when the apparatus is not used, the overall width of the apparatus is smaller than the original width. This makes it possible to provide a small-sized document reading device which is convenient for carrying.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a document reading apparatus according to an embodiment of the present invention.

FIG. 2 is a perspective view at the time of use of FIG. 1;

FIG. 3 is a perspective view of FIG. 1 when not in use.

FIG. 4 is a configuration diagram of a conventional document reading apparatus.

FIG. 5 is a perspective view of FIG. 4;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Original, 1a ... Read line, 2 ... Read window, 3 ... Line image sensor, 4 ... Lens, 5
a, 5b, 6 ... linear light sources.

Claims (1)

(57) [Claims] 1. An original reading apparatus which intermittently conveys an original in a sub-scanning direction and reads a reading line in a main scanning direction by a line image sensor, comprising at least two linear light sources having a length equal to or less than the length of the reading line. One or more reading lines are arranged in parallel with each other. When reading a document, the linear light source illuminates the reading lines from different angles with respect to the document surface, and when not reading, reduces to one illumination range of the linear light source. A document reading device.