KR20100103983A - Compact imaging apparatus having transparent window and illuminator - Google Patents

Abstract

PURPOSE: A compact imaging device having transparent window and illuminator are provided to supply compact imaging device, a compact imaging device that photographs comparatively large size subject by a comparatively small size imaging device. CONSTITUTION: A housing has a transparent plate(330) which is exposed to one part of upper surface by arranged diagonally. A first reflective mirror(310) is attached to lower surface of upper plate of the housing. A second reflective mirror(320) is attached to upper surface of lower plate of the housing. A camera(300) is arranged to photograph the subject, a subject that will be arranged to the transported plate, through a first reflective mirror and the second reflective mirror. A illuminating means is arranged to illuminate the transparent.

Description

Compact Imaging Apparatus Having Transparent Window And Illuminator

The present invention relates to a digital camera-based imaging device, and more particularly to a compact imaging device having a transparent window on which the subject is placed and an illuminator for illuminating the subject placed on the transparent window.

Digital camera-based imaging devices are used in various fields to capture identification cards, business cards, receipts, documents and the like and convert necessary information into digital data.

Conversion to digital data is performed by various processes such as character recognition and code recognition. Such devices are constantly being improved for the purpose of short processing time and accurate processing results.

Digital camera-based imaging devices are preferred because they can achieve a much faster imaging speed than other imaging devices. The disadvantage is that the quality of captured images is poor compared to line-based device-based scanners. Since poor image quality can cause errors in processing results, developers of digital camera-based imaging devices continue to make efforts to improve image quality.

The digital camera-based imaging apparatus determines an appropriate depth of field in consideration of the size of the subject and the imaging angle of the camera, and prevents image blur due to dithering by capturing the subject while the subject is left at the determined depth.

In addition, in a digital camera-based imaging device, an illuminator for illuminating the subject is disposed to obtain a high quality image by increasing the intensity of light reflected from the subject and incident on the camera.

A common method used to photograph a subject with a fixed depth of field at a fixed distance is to make a box including a camera mount and a transparent window, and to photograph the subject while the subject is placed on the transparent window. The problem is that in order to capture the subject within the camera's fixed imaging angle, an appropriate depth of field must be secured between the camera and the transparent window, which increases the size of the box.

The present invention seeks to provide a compact imaging device in which the physical size of the box is reduced while the depth of field between the camera and the transparent window is sufficiently secured.

On the other hand, while preventing the incident of other light rays except the light reflected from the subject to the camera, a high quality image can be obtained only when the intensity of the light reflected from the subject and incident on the camera is strong.

In order to increase the intensity of the light reflected from the subject and incident on the camera, an illuminator is arranged to illuminate the subject. When light emitted from the illuminator is incident directly on the camera or reflected from another part of the subject and is incident on the camera, The quality is very poor.

In particular, in a compact imaging device, optical elements such as reflectors are disposed, and a box for accommodating such optical elements, a transparent window, and a camera is also manufactured. The light from the illuminator is reflected from the optical element and the inner surface of the box to be incident on the camera. There is a problem of poor image quality.

Therefore, another object of this invention is to configure the illuminator and position the optical element so that light from the illuminator can be reflected from the inner surface of the optical element and the box to prevent or minimize the incident on the camera.

According to this invention, a housing having a transparent plate disposed obliquely and exposed to a part of the upper surface, a first reflecting mirror attached to the lower surface of the upper plate of the housing, a second reflecting mirror attached to the upper surface of the lower plate of the housing, and a first An imaging device including a camera disposed to have an optical axis orthogonal to the transparent plate via a reflecting mirror and a second reflecting mirror, and illumination means arranged to illuminate the transparent plate is provided.

Preferably, the plane including the mirror surface of the first reflector and the plane including the mirror surface of the second reflector may be disposed parallel to each other.

Preferably, the luminaire may be arranged between the first reflector and the camera.

Preferably, the luminaire may comprise light emitting means arranged in the illuminating chamber and a light exit slot configured to emit light generated by the light emitting means toward the transparent plate.

Preferably, the light exit slot may be configured to inject direct light over the entire surface of the transparent plate and form a shaded area where direct light does not reach the area where the first reflector and / or the second reflector is disposed.

Preferably, the optical axis of direct light emitted through the light exit slot may be configured to form an angle within ± 20 degrees with the mirror surfaces of the first reflector and the second reflector.

Preferably, the optical axis of the direct light emitted through the light exit slot and the optical axis of the camera may be configured to form an internal angle within 90 degrees.

Preferably, the extension lines of both wall surfaces of the light exit slots may be configured to coincide with both ends of the transparent plate, respectively.

Preferably, it may be possible to install a parallax at the exit of the light exit slot to increase the depth of the light exit slot.

According to this invention, a housing having a transparent plate disposed obliquely and exposed to a part of the upper surface, a first reflector attached to the lower surface of the upper plate of the housing, a second reflector attached to the upper surface of the lower plate of the housing, and a first An imaging device including a camera arranged to have an optical axis orthogonal to the transparent plate via a reflecting mirror and a second reflecting mirror has a relatively small size since the physical size of the imaging device is very small compared to the depth of field between the camera and the transparent window. The imaging device of the present invention can provide a compact imaging device capable of imaging a relatively large sized subject.

In addition, in the image pickup apparatus according to the present invention including the lighting means arranged to illuminate the transparent plate, the object placed on the transparent plate is sufficiently illuminated, so that a high-quality captured image can be obtained.

In addition, the lighting means includes a light emitting means disposed in the lighting chamber, and a light emitting slot configured to emit the light generated by the light emitting means toward the transparent plate, wherein the light emitting slot injects direct light over the entire surface of the transparent plate, In the image pickup apparatus according to the present invention, configured to form a shaded area where direct light does not reach the region where the reflector, the second reflector, and the camera are disposed, the light emitted from the luminaire is reflected from an object other than the subject and is incident on the camera. Since it is suppressed, a high quality picked-up image will be obtained.

Further, in the image pickup apparatus according to the present invention, in which the optical axis of the direct light emitted through the light exit slot forms an internal angle within ± 20 degrees of the mirror surfaces of the first reflector and the second reflector, not only the direct light from the luminaire but also the diffracted light may be Since reflection from an object and being incident on the camera are suppressed, a higher quality captured image may be obtained.

Referring now to the drawings, a preferred embodiment of the imaging device according to the present invention will be described in detail.

1 shows a perspective view of an imaging device 100 according to a preferred embodiment of the present invention. The imaging device 100 according to this embodiment has a substantially rectangular parallelepiped shape and includes a front plate 110, a rear plate 120, a seat plate 130, a right plate 140, an upper plate 150, and a lower plate 160. It has a housing, a portion of the top plate 150 is open, and the open area of the top plate 150 is blocked by the transparent plate 330 obliquely arranged extending from the top plate 150 to the back plate 120.

The transparent plate 330 serves as a holder for placing a subject such as an ID card or a business card, and the size of the housing may be appropriately changed according to the size of the transparent plate 330. In the imaging apparatus 100 according to the preferred embodiment, when the size of the transparent plate 330 is 9 cm × 6 cm, the left and right lengths of the lower plate 160 are about 10 cm, and the front and rear widths are about 9 cm, and the height of the side plate is about 100 cm. May have a size of about 4.5 cm.

The housing of the imaging device 100 may be formed of two or more pieces by appropriately molding two or more plates in consideration of molding convenience.

FIG. 2 is a view illustrating the interior of the imaging apparatus 100 in a state in which the seat plate 130 of the housing is removed, and FIG. 3 is an imaging apparatus 100 in a state in which the seat plate 130 and the right plate 140 of the housing are removed. 4 is an image showing the inside of the housing, and the front plate 110, the rear plate 120, the seat plate 130, the right plate 140, the upper plate 150, the lower plate 160 in the state of removing all 5 is a perspective view of the left side of the housing, and FIG. 6 is a cross-sectional view taken from the center of the left and right lengths of the housing to show the interior of the imaging device 100.

The interior of the housing is divided into an optical chamber 210, an accessory chamber 220, and an illumination chamber 230 by the partition wall 170.

The optical chamber 210 properly guides the path of light incident on the lens of the camera 300 in front of the transparent plate 330 to capture an image of a subject placed on the transparent plate 330 with the camera 300. It is comprised, and the 1st reflector 310 and the 2nd reflector 320 are arrange | positioned as an optical element.

The first reflecting mirror 310 is attached to the lower surface of the upper plate 150, the second reflecting mirror 320 is attached to the upper surface of the lower plate 160, in the imaging device 100 according to a preferred embodiment of the present invention The plane on which the first reflector 310 is disposed and the plane on which the second reflector 320 is disposed are parallel to each other.

In the accessory chamber 220, various components including various electrical and electronic devices and wirings are arranged.

The illumination chamber 230 is for illuminating a subject to be disposed on the optical chamber 210, in particular, the transparent plate 330, and includes an illumination plate 340. The lighting plate 340 may be a board in which LEDs or planar light emitters are appropriately arranged, or the lighting plate 340 may be a planar light emitter. The light emitted from the lighting plate 340 is emitted from the lighting room through the light emission slot 240 to illuminate the transparent plate 330. All or part of the inner surface of the lighting chamber 230 defined by the lighting plate 340 and the partition wall 170 may be reflective coated to reflect light.

As illustrated in FIG. 7, the camera 300 mounted on the board 301 and inserted into the optical chamber 210 from the accessory chamber 220 may pass through the first reflecting mirror 310 and the second reflecting mirror 320. It is arranged to have an optical axis orthogonal to 330. Since the optical axis of the camera 300 is orthogonal to the transparent plate 330, the distances of the light paths incident on the lens of the camera 300 are the same at all points on the transparent plate 330 having the same distance from the orthogonal point. FIG. 8 illustrates a ray path incident on the lens of the camera 300 at the center and both ends of the transparent plate 330.

As shown in FIG. 9, the light emitted from the lighting plate 340 may be formed by first and third edges 243 and 244 including the first edge 241 and the second edge 242. The transparent plate 330 is illuminated by exiting the lighting chamber 230 through the slot 240 defined by the second wall surface. The area indicated by the reference numeral 410 represents an area illuminated by direct sunlight from the lighting plate 340. The biggest and direct influence on the luminance of the illuminated transparent plate 330 is direct sunlight, and the light emitting area of the lighting plate 340 that can be emitted through the slot 240 is indicated by the reference numeral 400. It is limited to some areas near the center of (). Therefore, it is preferable that the illumination plate 340 and the illumination chamber 230 be configured to have as much light intensity as possible to emit or reflect in the light emission area 400 of the illumination plate 340.

As shown in FIG. 10, the illumination region 410 with direct sunlight should be limited within a range that does not invade effective regions of the first reflector 310 and the second reflector 320. The illumination area 410 may be defined by an appropriate combination of the thickness of the partition wall 170 forming the slot 240 and the width of the slot 240. A first shaded zone 420 is formed below the illumination area 410 and is blocked by the partition wall 170 without direct sunlight passing through the slot 240, and a second shaded area (above the illumination area 410 is formed). 430 occurs. The first reflecting mirror 310 and the camera 300 are disposed in the first shadowed zone 420, and the second reflecting mirror 320 is disposed in the second shadowed zone 430. That is, the direct light emitted from the lighting chamber 230 through the slot 240 is incident only on the transparent plate 330, and is not incident on the camera 300, the first reflector 310, and the second reflector 320. .

In FIG. 11, the intensity of the light waves diffracted by the light exiting from the illumination chamber 230 through the slot 240 is illustrated by dotted lines. As shown, in the imaging apparatus 100 according to the preferred embodiment of the present invention, a relatively strong diffraction light wave reaches the first reflector 310, and a relatively weak diffraction light wave reaches the second reflector 320 and the camera 300. Reaches. In order to obtain a high quality image with uniform illuminance, it is preferable that the diffracted light waves of uniform intensity reach the entire surface of each of the reflectors 310 and 320 rather than the intensity of the diffraction light waves reaching the respective reflectors 310 and 320. It is important. In the image pickup apparatus 100 according to the illustrated exemplary embodiment, an optical axis emitted through the slot 240 has an angle (b, c) within ± 20 degrees of the mirror surfaces of the first reflector 310 and the second reflector 320. Or nearly parallel, the diffracted light waves reaching each of the first reflector 310 and the second reflector 320 are nearly uniform across the entire surface of each reflector 310, 320. This is because the farther away from the exit of the slot 240, the weaker the intensity of the diffraction light waves becomes, but the divergence angle of the isolines of the diffraction light waves intensity becomes wider.

It is preferable that not only the direct light but the diffracted light wave do not reach the lens of the camera 300. In order to reduce the arrival of the diffracted light wave to the lens of the camera 300, as shown in FIG. 12, the angle a between the optical axis of the camera and the optical axis emitted through the slot should be as narrow as possible. In a preferred embodiment, this angle a is made into 90 degrees or less.

On the other hand, it is also possible to replace the illustrated lighting chamber 230 or to install the lighting chamber in another location, for example, the regions 230A and 230B shown in FIG. However, the light emitted from the lighting room should be strictly prohibited from entering the first reflector 310, the second reflector 320, and the camera 300, and the first reflector 310 and the second reflector should be strictly prohibited. The diffraction light waves arriving at 320 must be uniform across the front of each reflector and the diffraction light waves arriving at the lens of the camera 300 should be reduced as much as possible.

Like the imaging device 100 according to the preferred embodiment of the present invention as shown, when the illumination chamber 230 is installed between the first reflector 310 and the camera 300, the illumination chamber 230 Although a portion of the direct light emitted from the light incident on the transparent plate 330 is reflected by the transparent plate 330, it is hardly incident on the first reflector 310, the second reflector 320, and the camera 300. When the illumination chamber 230 is installed at another position, the direct light emitted from the illumination chamber 230 and incident on the transparent plate 330 is reflected by the transparent plate 330 to reflect the first reflector 310 and the second reflector. It should be configured to prevent or uniformly minimize incident to the 320 or the camera 300. Without reflecting the bottom surface of the transparent plate 330 without damaging the transparency of the transparent plate 330, the direct light incident on the transparent plate 330 is reflected by the transparent plate 330, the first reflector 310, the second It may be prevented or minimized to be incident on the reflector 320 or the camera 300.

FIG. 13 is an enlarged view of the lighting chamber 230 to explain the configuration of the slot 240. The slot 240 has a narrow inlet, ie between the first edge 241 and the third edge 243, and an outer outlet, ie a second edge, to diverge the outgoing light to illuminate the transparent plate 330 evenly. It is preferable to form a wide space between 242 and the fourth edge 244. The divergence angle includes an extension line of the slot wall surface defined by the first edge 241 and the second edge 242 and an extension line of the slot wall surface defined by the third edge 243 and the fourth edge 244. It is preferable to form the same at both ends of 330, respectively. The width of the slot 240 should be limited so that the outgoing direct rays of light do not invade the effective areas of the first reflector 310 and the second reflector 320. In other words, direct sunlight passing between the third edge 243 and the second edge 242 should not enter the first reflector 310, but pass between the first edge 241 and the fourth edge 244. One direct ray should not be incident on the second reflector 320. To do so, the width of the slot 240 is as narrow as possible in view of the distance between the first edge 241 and the second edge 242 and the distance between the third edge 243 and the fourth edge 244. Should. The thickness of the partition wall 170 in the vicinity of the slot 240 is thick, or as shown in FIG. 14, the additional edges 245 and 246 are installed at the outlet of the slot 240 to between the first edge 241 and the second edge 242. If the distance between the third edge 243 and the fourth edge 244 is sufficiently long, the width of the slot 240 may be wide, and a relatively large amount of direct sunlight can be illuminated on the transparent plate 330. There will be.

While the invention has been described in connection with specific embodiments, examples, dimensions, and the like, this is merely illustrative to aid in understanding the purpose, features, and advantages of the invention, and is well understood by those of ordinary skill in the art. It will be readily apparent to those skilled in the art that changes or modifications from the illustrated embodiments can be made without departing from the spirit and scope of the invention as set forth in the claims. It is to be understood that the scope of the claims is to cover such changes or modifications.

1 is a perspective view of an image pickup apparatus according to a preferred embodiment of the present invention.

Fig. 2 is a diagram showing the inside of the imaging device in a state where the seat plate of the housing is removed.

3 is a view showing the inside of the imaging device in a state where the left and right plates of the housing are removed.

4 is a view showing the inside of the imaging device in a state where all of the front plate, the rear plate, the seat plate, the right plate, the upper plate, and the lower plate of the housing are removed.

5 is a perspective view seen from the left side of the housing.

6 is a cross-sectional view taken at the center of the left and right lengths of the housing to show the interior of the imaging device.

FIG. 7 illustrates a relationship between an optical axis of the camera and a transparent plate in a view similar to FIG. 6.

FIG. 8 is a view similar to FIG. 6, showing a ray path incident on a lens of a camera at the center and both ends of the transparent plate.

FIG. 8 shows a ray path incident on the lens of the camera at the center and both ends of the transparent plate.

FIG. 9 is a view similar to that of FIG. 6, in which light rays emitted from an illumination chamber illuminate the transparent plate.

FIG. 10 shows the illumination area and the shaded area of the light rays emitted from the illumination chamber in a view similar to FIG. 9.

FIG. 11 shows the intensity of diffraction light waves of light emitted from the illumination chamber in a view similar to FIG. 6.

FIG. 12 illustrates a relationship between a slot of a lighting room and a camera in a view similar to FIG. 6.

13 is an enlarged view of the configuration of the lighting chamber according to the preferred embodiment of the present invention.

14 is an enlarged view of a configuration of a lighting room according to another embodiment of the present invention.

Claims (11)

A housing having a transparent plate disposed obliquely and exposed to a part of the upper surface; A first reflector attached to a lower surface of the upper plate of the housing; A second reflector attached to an upper surface of the lower plate of the housing; A camera arranged to photograph a subject to be disposed on the transparent plate via the first reflector and the second reflector; And illuminating means arranged to illuminate the transparent plate. The method according to claim 1, And a plane including the mirror surface of the first reflector and a plane including the mirror surface of the second reflector are arranged in parallel with each other. The method according to claim 1, And said illuminating means is disposed between said first reflecting mirror and said camera. The method according to claim 1, 2 or 3, Light emitting means in which the luminaire is disposed in an luminaire; And an output light slot configured to emit light generated by the light emitting means toward the transparent plate. The method according to claim 4, And the illuminating means is configured to inject direct light over the entire surface of the transparent plate and form a shaded area in which direct light does not reach a region where the second reflector is disposed. The method according to claim 5, And the illuminating means is configured to inject direct light over the entire surface of the transparent plate and form a shaded area in which direct light does not reach a region where the first reflector is disposed. The method according to claim 5, And an end face of the slot is inclined so that light reflected by the end face of the light exit slot does not enter the first reflector and the second reflector. The method according to claim 5, And an optical axis of direct light emitted through the light exit slot forms an internal angle within ± 20 degrees of mirror surfaces of the first reflector and the second reflector. The method according to claim 5, And an optical axis of direct light emitted through the light exit slot and an optical axis of the camera to form an internal angle within 90 degrees. The method according to claim 5, And the extension lines of both wall surfaces of the light exit slots coincide with both ends of the transparent plate, respectively. The method according to claim 5, And an additional edge is provided at the exit of the light exit slot to increase the depth of the light exit slot.

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