JPH10190979A - Reflection optical unit and scanner optical system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make the size and the profile of the scanner optical system small and thin by combining a plurality of 4-side reflection optical systems consisting of two sets of parallel planes. SOLUTION: Two optical blocks 14, 16 are placed facing opposite to each other and a 4-side reflection optical system consisting of two sets of parallel reflection faces 32, 34 and 36, 38, and a 4-side reflection optical system consisting of two sets of parallel reflection faces 42, 44 and 46, 48 are formed vertically. A light from an original 30 lit by a light source 27 is received from an incident port 50, reflected at least once in each reflecting face and emitted from an emission port 52, and then led into a CCD 20 via a lens 18. Through such a constitution, the thickness in the horizontal direction in a figure is reduced more in comparison with the case that the same optical length is formed by one 4-side optical reflection optical system.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reflection optical unit and a scanner optical system, and more particularly to a reflection optical unit for forming an optical path disposed between an object to be photographed and a lens to secure a required conjugate length. The present invention relates to a unit and a small scanner optical system including the reflection optical unit.

[0002]

2. Description of the Related Art In a handy scanner that illuminates a document with a light source for illumination and captures image information while moving along the document, light from a document surface incident from a reading opening (slit) is passed through a lens. It leads to a line sensor (CCD). Conventionally, a plurality of folding mirrors are provided in the casing of the scanner in order to secure such a conjugate length.

[0003]

However, in the above-described conventional scanner optical system, the angle adjustment of mirrors provided to secure a necessary conjugate length is delicate, and a plurality of mirrors are set at an appropriate angle. It is extremely difficult to attach. Further, when the number of times of folding is increased, the number of mirrors is increased, and it is difficult to further reduce the size.

The present invention has been made in view of such circumstances, and provides a reflecting optical unit for forming an optical path, which does not require fine adjustment of the angle of the reflecting surface and can achieve further downsizing. An object of the present invention is to provide a scanner optical system suitable for a small-sized handy scanner by applying such a reflection optical unit.

[0005]

In order to achieve the above object, the present invention reflects a light beam incident on an area surrounded by two sets of parallel planes at least once on each plane of the parallel planes and emits the reflected light. The present invention is characterized in that a plurality of four-surface reflecting optical systems are combined. That is, 4 of two sets of parallel planes
The surface reflection optical system can increase or decrease the number of reflections by changing the length ratio of two sets of parallel planes, and can form a relatively long optical path length in a region surrounded by the parallel planes. There is an advantage. By providing a plurality of such four-sided reflection optical systems, a longer optical path length can be achieved without increasing the size of one four-sided reflection optical system. Rather, the thickness can be reduced.

As described above, according to the present invention, even when a long optical path length is required, there is no need to add a mirror for folding back and the like, and there is an advantage that the optical system can be downsized. Further, when a plurality of four-surface reflecting optical systems are formed by arranging two optical blocks each having a reflecting surface facing each other, the optical blocks may be formed to have the same shape as each other. is there. In such a case, there is an advantage that both blocks can be manufactured in a common mold.

Furthermore, one of the four-sided reflection optical system or a plurality of the four-sided reflection optical system is used as a basic structural unit, and each basic structural unit is modularized, so that a plurality of basic structural units are connected. Accordingly, it is possible to cope with various modes, and it is possible to reduce the number of parts. Further, in order to achieve the above object, the present invention provides a scanner optical system which guides light from a photographing object illuminated by a light source to an image pickup means via a lens, within an area surrounded by two sets of parallel planes. At least one incident light beam is incident on each of the parallel planes.
A reflection optical unit comprising a combination of a plurality of four-sided reflection optical systems for reflecting and emitting light, and configured to guide light from the object to be photographed to the lens via the reflection optical unit. And

According to the present invention, the above-mentioned reflecting optical unit is applied to a scanner optical system. According to this configuration, the angle adjustment of the reflection surface is unnecessary or easy, and the optical axis can be easily adjusted, and further, the size and thickness can be further reduced.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a scanner optical system according to the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a sectional view of a handy scanner to which a scanner optical system according to the present invention is applied, and FIG. 2 is a front perspective view thereof.

The scanner 10 shown in FIG. 1 includes a casing 12, in which a reflection optical unit 14, a lens 18, a line sensor (CCD) 20, a scanner circuit 22, a roller 24 for position detection, and the like are arranged. Note that reference numeral 26 is C
It is a CD substrate. The reflection optical unit 14 includes two optical blocks 15, 1 formed of transparent optical plastic.
Consists of six. The optical blocks 15 and 16 are made of optical plastic because they are lighter in weight and easier to process and mold than glass.

On the left side of the optical block 15, four reflection surfaces are formed in a W-shape. That is, from below, a reflecting surface 32 having a length A, a reflecting surface 36 having a length B (> A) orthogonal thereto, a reflecting surface 48 having a length B orthogonal to the reflecting surface 36, and the reflecting surface 32 Reflecting surface 4 of length A orthogonal to 48
4 are formed. On the other hand, four reflection surfaces are formed in a W-shape also on the right side surface of the optical block 16.
That is, from below, a reflecting surface 38 having a length B, a reflecting surface 34 having a length A orthogonal to the reflecting surface 38, a reflecting surface 42 having a length A orthogonal to the reflecting surface 34, and orthogonal to the reflecting surface 42. A reflecting surface 46 having a length B is formed. Each of the reflecting surfaces 3
2, 34, 36, 38, 42, 44, 46, 48
It has a silver deposition coating.

The two optical blocks 15 and 16 have a predetermined distance d.
, And the reflecting surface 32 and the reflecting surface 34 face in parallel with each other to form a set of parallel reflecting surfaces. Similarly, the reflecting surfaces 36 and 38, the reflecting surfaces 42 and 44, and the reflecting surfaces 46 and 48 are disposed so as to face in parallel to each other. With this configuration, a four-sided reflecting optical system including the reflecting surfaces 32, 34, 36, and 38 and a four-sided reflecting optical system including the reflecting surfaces 42, 44, 46, and 48 are continuously formed vertically. .

Since the two optical blocks 15 and 16 are arranged at an interval of a distance d, a light beam entrance 50 is formed at the intersection of the reflection surface 32 and the reflection surface 38, and the reflection surface 34 An emission port 52 is formed at the intersection of the reflection surface 38. The entrance 50 and the exit 52 are connected to each reflection surface 32,
38, 44, and 46 are formed so as not to hinder the reflection.

As described above, by limiting the width of the entrance port 50, it is possible to prevent unnecessary light from entering while securing necessary light incidence. Further, there is an advantage that an appropriate amount of emitted light can be obtained according to the width of the emission port 52. If the width of the exit 52 is small, the amount of light in the sagittal direction decreases and the resolution decreases. Therefore, it is necessary to determine the width of the exit 52 so that a sufficient amount of light in the sagittal direction can be obtained.

On the left side of the optical block 16 in the figure, a concave portion (light source disposing portion) for assembling a light source 27 for illuminating a document.
A light source 27 such as a light emitting diode (LED) array is arranged in the concave portion 28. Light source 27
Enters the optical block 16, passes through the block, and is emitted from the illumination light exit surface 29 toward the original 30. The light source 27 is not limited to the LED array, but may be a linear fluorescent lamp.

On the bottom surface of the casing 12, a slit is formed just below the entrance 50 of the reflection optical unit 14, and the light emitted from the illumination light exit surface 29 passes through the slit through the document. 30 is irradiated. Light from the document 30 is guided from the slit into the casing 12 and enters the reflection optical unit 14 from the entrance 50.

The light incident on the reflection optical unit 14 is reflected by the reflection surface 36 to the left by 90 degrees in the figure, and thereafter reflected in the order of the reflection surfaces 34, 38, 36, 32, and 38. The light is emitted from the reflection optical system toward the upper four-side reflection optical system. The light incident on the upper four-sided reflecting optical system is reflected by the reflecting surface 46 to the right by 90 degrees in the drawing, and thereafter, the reflecting surface 4
The light is reflected in the order of 4, 48, 46, 42, and 48, and is finally emitted from the emission port 52 to the outside of the reflection optical unit 14.

A lens 18 and a CCD 20 are disposed above the light exit 52 of the reflection optical unit 14. Light emitted from the reflection optical unit 14 passes through the lens 18 to the C light source.
Guided to CD20. The light incident on the light receiving surface of the CCD 20 is converted into an electric signal according to the light intensity, and the electric signal is guided to the scanner circuit 22. Then, information of the document image is obtained by the image signal processing means of the scanner circuit 22.

The position detecting roller 24 disposed below the casing 12 is provided with a means (not shown) for detecting the number of revolutions of an encoder or the like so that the position and amount of movement of the scanner 10 can be determined. It can be detected.
Next, the operation of the handy scanner to which the scanner optical system according to the present invention configured as described above is applied will be described.

First, the reflection function of a four-surface reflecting optical system composed of two sets of parallel planes will be described. FIG. 3 to FIG.
It is explanatory drawing which modeled the four-surface reflection optical system which consists of a set of parallel planes. A set of parallel reflective surfaces 32, 34 of length A
And a pair of parallel reflecting surfaces 36 and 38 each having a length B (> A). In a four-surface reflecting optical system in which these two sets of parallel planes are orthogonal to each other, the lowermost part shown by a white circle in the drawing. The reflection optical path in the case where light enters from the vertex (incident point) will be described in relation to the length ratio (A: B).

FIG. 3 shows a situation where A: B = 3: 4. Light that has entered the reflective optical unit 14 upward from the incident point indicated by the white circle in the drawing is reflected by the reflective surface 36 (hereinafter, referred to as a first surface).
(Referred to as a reflective surface) and reflected 90 degrees to the right in the figure.
Reflection surface 34 (hereinafter, referred to as a second reflection surface), reflection surface 38
(Hereinafter, referred to as a third reflecting surface), a reflecting surface 32 (hereinafter, referred to as a fourth reflecting surface).
(Referred to as a reflection surface) in this order, and the light is finally reflected again by the first reflection surface 36, and is emitted out of the reflection optical unit 14 from the right end vertex (emission point) indicated by a black circle in the drawing. In this case, the total number of reflections is 5 and the optical path length is 4 × 2
^1/2 × A.

FIG. 4 shows a state where A: B = 3: 5. Light that has entered the reflective optical unit 14 upward from the incident point indicated by the white circle in the drawing is reflected by the first reflection surface 36 at 9 in the drawing.
The light is reflected rightward by 0 degrees, and thereafter reflected in the order of the second reflecting surface 34, the third reflecting surface 38, the first reflecting surface 36, the fourth reflecting surface 32, and the third reflecting surface 38. Are emitted out of the reflection optical unit 14 from the vertex (emission point). In this case, the total number of reflections is 6, and the optical path length is 5 × 2 ^1/2 × A.

FIG. 5 shows a state where A: B = 4: 5. Light that has entered the reflective optical unit 14 upward from the incident point indicated by the white circle in the drawing is reflected by the first reflection surface 36 at 9 in the drawing.
The light is reflected rightward by 0 degrees, and thereafter, the second reflecting surface 34, the third reflecting surface 38, the fourth reflecting surface 32, the first reflecting surface 36, and the second
The light is reflected in the order of the reflection surface 34 and the third reflection surface 38, and the reflection optical unit 14 starts from the left vertex (emission point) indicated by a black circle in the drawing.
It is emitted outside. In this case, the total number of reflections is 7, and the optical path length is 5 × 2 ^1/2 × A.

FIG. 6 shows a state where A: B = 3: 7. Light that has entered the reflective optical unit 14 upward from the incident point indicated by a white circle in the drawing is at least 1 at each reflective surface.
The light is reflected once, and is emitted out of the reflective optical unit 14 from the upper emission point indicated by a black circle in the figure after a total of eight reflections. In this case, the optical path length is 7 × 2 ^1/2 × A. As described above, by changing the ratio of A: B, the reflection path and the number of reflections are changed, and the emission direction can be changed as appropriate to the right, left, and upward directions, and the optical path length can be changed as appropriate. . The ratio to be used is determined according to the required conjugate length and the positional relationship between the entrance 50, the lens 18 and the CCD 20.

With this configuration, the number of reflections can be increased or decreased in accordance with the ratio (A: B) of the lengths of the two parallel reflecting surfaces, and a relatively long optical path length can be obtained without adding a conventional folding mirror. Can be formed. Thereby, there is an advantage that a fine angle adjustment of the mirror is not required, and further downsizing can be achieved. In the embodiment shown in FIG. 1, a system in which two above-described four-surface reflecting optical systems are continuously combined vertically is employed (see FIG. 7).
As described above, by providing the four-sided reflection optical system continuously in the vertical direction, the thickness in the left-right direction in the figure is reduced as compared with the case where one four-sided reflection optical system forms the same optical path length. There is an advantage that can be. In particular, when two four-sided reflection optical systems shown in FIG. 4 are connected as shown in FIG. 7, the input optical axis and the output optical axis can be made to coincide on the same axis, and the optical axis adjustment is easier. There is an advantage.

When the scanner 10 having such a reflection optical unit is moved in one direction (to the right or the direction in the figure) along the surface of the original 30, the rollers 24 rotate while contacting the original 30, and the scanner 24 is rotated. The distance between the document 10 and the surface of the document 30 is kept constant, and the scanner 10 moves smoothly. Then, based on the rotation of the roller 24, the scanner 1
While detecting the position of 0, the light from the surface of the original 30 is sequentially transmitted through the above-mentioned reflecting optical unit 14 and the lens 20 to C.
By guiding to the CD 20, image information of the document 30 can be obtained.

In the above-described embodiment, the case where the four-sided reflection optical system is formed in two stages vertically has been described as an example, but two four-sided reflection optical systems may be provided on the left and right as shown in FIG. . That is, FIG. 8 shows a combination of the two four-side reflection optical systems shown in FIG. 3 in the horizontal direction, and the optical block 55 and the optical block 56 are formed in the same shape. By rotating one optical block 55, the other optical block 56
And both blocks can be made in the same mold.

As described above, the left and right optical blocks 55, 5
6 has a rotationally symmetrical shape and can be molded with the same mold, so that there is an advantage that the manufacturing cost can be greatly reduced. Further, when the four-surface reflecting optical system is continuously provided on the left and right as shown in FIG. 8, there is an advantage that the thickness in the vertical direction in FIG. 8 can be reduced. In the above embodiment, the case where two four-sided reflection optical systems are formed has been described. However, as shown in FIG. 9, three four-sided reflection optical systems are formed by two opposing optical blocks 57 and 58. The number of combinations is not limited as long as it is two or more.

Further, the reflecting optical unit shown in FIG.
It is also possible to form more various reflection optical paths by combining with the reflection unit shown in FIG. That is, FIG.
Considering the reflective optical unit as shown in FIG. 8 as a basic constituent unit, and combining and combining these arbitrarily, various types of reflective optical units can be formed.

Similarly, various four-surface reflecting optical systems constituted by two sets of parallel planes as shown in FIGS. 3 to 6 are constituted by a pair of optical blocks and the like, and these are included in the basic structural unit. Is also good. Thus, one of the four-sided reflection optical system or the four
By using a plurality of couplings of the surface reflection optical system as basic structural units and modularizing each basic structural unit, it is possible to reduce the number of types of components and to cope with various modes.

Therefore, for example, when it is difficult to form a linear optical path due to the layout including other members such as the lens 18 and the position detecting roller 24, a combination of different types of optical blocks is appropriately used. There is an advantage that can be. In the above-described embodiment, the case where one set of parallel reflecting surfaces 32 and 34 and another set of parallel reflecting surfaces 36 and 38 form 90 degrees with each other is described. The angle is not limited to 90 degrees, but may be 60 degrees or 120 degrees as shown in FIG.

Further, in the above embodiment, the entrance 50
And a vertical scanner in which the lens 18 and the CCD 20 are arranged substantially linearly in the vertical direction as an example, but a horizontal type using a reflection optical unit that emits light incident from below in the orthogonal direction (horizontal direction). The present invention can be applied to a scanner.

[0033]

As described above, according to the reflecting optical unit of the present invention, a plurality of four-side reflecting optical systems that reflect at least once on each of two parallel planes are provided continuously. A relatively long optical path length can be formed in the space surrounded by the parallel planes, and the thickness can be reduced as compared with the case where one four-sided reflection optical system is used. In addition, the conventional fine adjustment of the angle of the folding mirror becomes unnecessary, and further downsizing can be achieved.

When the plurality of four-sided reflection optical systems are formed by arranging two optical blocks to face each other, there are cases where these two optical blocks can be formed in the same shape. In such a case, both blocks can be manufactured with a common mold, and cost reduction can be achieved. In particular, one of the four-sided reflection optical system or a combination of a plurality of the four-sided reflection optical system as a basic structural unit,
Since each basic structural unit is modularized, it is not necessary to separately prepare reflective optical systems according to various forms,
There is an advantage that various forms can be accommodated by arbitrarily combining the basic constituent units. Thereby, the number of component types can be reduced.

Further, if the above-mentioned reflecting optical unit is applied to a scanner optical system, the angle adjustment of the reflecting surface becomes unnecessary or easy, and further reduction in size and thickness can be achieved.

[Brief description of the drawings]

FIG. 1 is a sectional view of a handy scanner to which a scanner optical system according to the present invention is applied.

FIG. 2 is a front perspective view showing a configuration of an optical system of the handy scanner shown in FIG.

FIG. 3 is a diagram used to explain a reflection path of a four-surface reflecting optical system having two sets of parallel reflecting surfaces having different lengths.

FIG. 4 is a diagram used to explain a reflection path of a four-surface reflection optical system having two sets of parallel reflection surfaces having different lengths.

FIG. 5 is a diagram used to explain a reflection path of a four-surface reflection optical system having two sets of parallel reflection surfaces having different lengths.

FIG. 6 is a diagram used to explain a reflection path of a four-surface reflection optical system having two sets of parallel reflection surfaces having different lengths.

FIG. 7 is an enlarged sectional view of the reflection optical unit.

FIG. 8 is an enlarged sectional view showing another embodiment of the reflection optical unit.

FIG. 9 is an enlarged sectional view showing another embodiment of the reflection optical unit.

FIG. 10 is a diagram showing a reflection path when two sets of parallel reflection surfaces are configured to form 60 degrees or 120 degrees.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Scanner 12 ... Casing 14 ... Reflection optical unit 15, 16, 55, 56, 57, 58 ... Optical block 18 ... Lens 20 ... Line sensor (CCD) 22 ... Scanner circuit 24 ... Roller for position detection 27 ... Illumination Light source 30 ... original document 32, 34, 36, 38, 42, 44, 46, 48 ... reflection surface 50 ... entrance port 52 ... exit port

Claims (4)

[Claims] 1. A combination of a plurality of four-surface reflecting optical systems for reflecting a light beam incident on a region surrounded by two sets of parallel planes at least once on each surface of the parallel planes and emitting the reflected light. Characteristic reflective optical unit. 2. A plurality of four planes comprising the two sets of parallel planes.
2. The reflection optical unit according to claim 1, wherein the surface reflection optical system is formed by a pair of optical blocks, and each of the optical blocks is formed in the same shape and can be formed by the same mold. 3. A reflection optical system module having at least one type of reflection optical system module having one of the four surface reflection optical systems or a combination of a plurality of the four surface reflection optical systems as a basic structural unit is formed. 2. The reflection optical unit according to claim 1, wherein the reflection optical unit is formed by combining the individual components. 4. A scanner optical system for guiding light from an object to be photographed illuminated by a light source to an image pickup means via a lens, wherein a light beam incident on an area surrounded by two sets of parallel planes is
A reflecting optical unit comprising a combination of a plurality of four-sided reflecting optical systems for reflecting and emitting at least once on each surface of the parallel plane, and transmitting light from the object to be photographed to the lens via the reflecting optical unit; A scanner optics configured to guide.