CN201011731Y - scanning device - Google Patents

Abstract

The utility model discloses a scanning device for scan the image of a file, it includes a casing, an at least plane of reflection, a base plate, a plurality of pointolite and an image sensing element. The top surface of the shell is provided with a slit, and the reflecting surface is arranged in the shell, extends to one side edge of the slit and faces the slit. The substrate is fixed on one side edge of the reflecting surface, and the point light sources are fixed on the substrate and are arranged at intervals along the direction parallel to the slit. The light sources of each point are used for projecting scanning light towards the reflecting surface, so that the scanning light is projected on the surface of the document through the slit after being reflected, is reflected to form image light, and then enters the shell through the slit. The image sensing element is arranged in the shell and used for receiving the image light reflected by the file and converting the image light into image data. Adopt the utility model discloses can effectively make the luminous intensity homogenization of the light that pointolite such as emitting diode sent, and can effectively reduce the problem that manufacturing cost is high and cold cathode tube is difficult for the operation.

Description

scanning device

technical field

The utility model relates to a scanning device, in particular to a scanning device which uses a plurality of point light sources to project scanning light.

Background technique

The main components of the scanning device include image sensing elements, light emitting elements and optical elements, wherein the optical elements are mainly used for reflection, refraction or focusing to change the path of light and focus the light on a specific area. The light-emitting element is used to project scanning light, so that the scanning light falls on the surface of the document, and the scanning light is reflected by the surface of the document to form image light, which is then received by the image sensing element and converted into image data.

Since the image sensing element must receive the image light before it can acquire the image and convert it into image data, the spectrum and intensity of the light emitted by the light emitting element are very important. The light spectrum must fall within a predetermined range, so that the reflected image light can correctly present the image color of the scanned document, so that the image sensing element can obtain a correct image. The light intensity must be sufficient so that the light intensity of the image light formed by the reflection is sufficient for the image sensing element to correctly capture the light intensity, and the light intensity must also be evenly distributed to avoid inconsistencies in brightness and darkness. Since the image sensing element is slender, and the image sensing element scans the page through a slit to obtain the entire page image, the ideal light emitting element is a line light source. Traditionally, cold cathode tubes are mostly used as light emitting elements. To obtain a line light source with uniform light intensity distribution and provide ideal white light. However, the cold-cathode tube has its disadvantages. The operating voltage of the cold-cathode tube is high and the initial start-up voltage is higher. A rectifier circuit must provide a high voltage to drive the cold-cathode tube, which increases the cost of the scanning device. Secondly, after the cold-cathode tube is turned on, it must wait for a period of time before the emitted light intensity tends to stabilize. That is to say, the scanning device using the cold-cathode tube must wait for a period of time to warm up after being turned on before operating. In addition, the luminous intensity of cold cathode tubes is greatly affected by temperature. If the temperature of the cold-cathode tube increases after the continuous operation of the scanning device, the intensity of the light emitted by it will also change, and even the frequency spectrum will shift, so that the emitted light is no longer ideal white light, resulting in inconsistent image scanning quality under continuous operation of the scanning device .

In addition to cold cathode tubes that can provide ideal white light, light-emitting diodes can also provide ideal white light, so they are also used in scanning devices as light-emitting elements that provide scanning light. Light-emitting diodes are not limited to white LEDs that can emit ideal white light. For example, the scanner in the utility model of Taiwan Patent No. TW518877 does not directly provide white light, but sequentially obtains red, green, and blue light with monochrome image sensing elements. Images of different colors are synthesized into a color image, which solves the problem of high cost of white LEDs and color image sensing components.

However, LEDs are point light sources, and the emitted light is distributed along a conical space, and the light intensity decreases with distance. To cover the entire scanning area, the LEDs must be arranged in a long array so that the emitted light can cover the entire scanning area. scan area. However, the area between two adjacent LEDs in the LED array can only rely on the scattering effect of the air to generate weak luminous flux. Therefore, if the scanning light is directly projected by the light-emitting diode array, the light intensity received by the scanning area will be inconsistent, and the aforementioned TW518877 does not propose a solution for the inconsistent light intensity.

To solve the problem that light-emitting diodes cannot provide line light sources, the existing method is to use elements such as prisms and transparent columns as light-guiding elements, and use light-emitting diodes to project light at both ends of the light-guiding element. , so that the light is evenly projected from the side of the light guide element. For example, the Chinese Taiwan patent No. TW549768 and TWI253840 patent case respectively propose to use the design of the light guide element to convert the light emitting diode into a line light source. The design of the light guide element still has its disadvantages. When the light travels in the light guide element, it will quickly decay. Therefore, the length of the light guide element must be limited, making it difficult to increase the page width of the scannable document. In addition, the high heat generated during the operation of the light-emitting diodes will easily degrade the material of the light guide element, making the material change from colorless and transparent to opaque or begin to appear color, and lose the light guide effect. Therefore, the design of the light guide element is adopted. It is still impossible to effectively solve the problem of using light-emitting diodes to provide scanning light sources.

Utility model content

The purpose of the utility model is to provide a scanning device to solve the problem that the light intensity distribution cannot be made uniform when a point light source is used as a scanning light source.

In order to achieve the above object, the utility model discloses a scanning device for scanning an image of a document, which includes a casing, at least one reflective surface, a substrate, a plurality of point light sources and an image sensing element. A slit is defined on the top surface of the shell. The reflective surface is disposed in the casing, extends on one edge of the slit, and faces the slit. The substrate is fixed on one edge of the reflective surface, and the point light sources are fixed on the substrate and arranged at intervals along a direction parallel to the slit. Each point light source is used to project a scanning light towards the reflective surface, so that the scanning light is reflected and projected on the surface of the document through the slit, and is reflected to form an image light, which then enters the casing through the slit. The image sensing element is arranged in the casing, and is used for receiving the image light reflected by the mirror and converting it into image data.

The efficacy of the utility model lies in that the light intensity of light emitted by point light sources such as light-emitting diodes can be effectively made uniform without adding additional components. The linear light source of the cold cathode tube is replaced by a plurality of point light sources, which effectively reduces the problems of high manufacturing cost and difficult operation of the cold cathode tube.

The above description about the contents of the utility model and the following description of the implementation are used to demonstrate and explain the principle of the utility model, and provide further explanation of the claims of the utility model.

Description of drawings

Figure 1A is a schematic cross-sectional view of the first embodiment of the utility model;

Figure 1B is a partially enlarged view of Figure 1A;

Fig. 1C is an exploded perspective view of some components in the first embodiment of the present invention;

Fig. 2 is the schematic diagram that a plurality of point light sources arranged at intervals emit light in the utility model;

Fig. 3 is a schematic diagram of the light intensity distribution of light emitted by a plurality of point light sources arranged at intervals in the utility model;

Fig. 4 is a schematic diagram of a plurality of point light sources arranged at intervals in the utility model emitting light and reflected by a reflective surface;

Fig. 5 is a schematic diagram of the light intensity distribution of a plurality of point light sources arranged at intervals in the present invention and reflected by the reflective surface;

6 is a schematic cross-sectional view of a paper-fed scanner applying the utility model;

Fig. 7 is a schematic cross-sectional view of a platform scanner applying the utility model;

Fig. 8A is a schematic cross-sectional view of the second embodiment of the present invention;

Figure 8B is a partially enlarged view of Figure 8A;

Fig. 9A is a schematic cross-sectional view of a third embodiment of the present invention;

Figure 9B is a partially enlarged view of Figure 9A; and

Fig. 9C is an exploded perspective view of some components in the third embodiment of the present invention.

Among them, reference signs:

100: Scanning device 110: Housing

111: Slit 112: Reflective surface

113: reflective layer 120: light emitting unit

121: Substrate 122: Point light source

130: Mirror 140: Focusing element

150, 150': image sensor 200: sheet-fed scanner

210: Body 211: Window

212: Transparent partition 220: Paper feeding device

221: paper track 222: opening

223: Auxiliary transparent partition 300: Flatbed scanner

310: Body 311: Transparent Partition

320: Mobile device S: Scanning light

D: File I: Image light

Detailed ways

In order to have a further understanding of the purpose, structure, features, and functions of the present utility model, the detailed description is as follows in conjunction with the embodiments.

Please refer to FIG. 1A and FIG. 1B , which are a scanning device 100 disclosed in the first embodiment of the present invention, which is used to scan an image of a document D and convert the image into image data. The scanning device 100 includes a casing 110 , a reflective surface 112 , a light emitting unit 120 , one or more mirrors 130 , a focusing element 140 , and an image sensing element 150 . A slit 111 is defined on the top surface of the housing 110 for light to pass through. The reflective surface 112 is disposed in the casing 110 and extends from one edge of the slit 111 toward the slit 111 . A reflective layer 113 is formed on the surface of the reflective surface 112 by coating or sticking, for allowing light to enter the reflective surface 112 , and to reflect the light through the slit 111 to project outside the casing 110 . The reflective surface 112 can be a plane to directly reflect the light, or a concave curved surface to focus the light at a predetermined position outside the casing 110 .

Referring again to FIG. 1A , FIG. 1B and FIG. 1C , the light emitting unit 120 includes a substrate 121 and a plurality of point light sources 122 . The substrate 121 is fixed on a corresponding side edge of the reflective surface 112, and a plurality of point light sources 122 are fixed on the substrate 121 and arranged in a row along a direction parallel to the slit 111, as shown in FIG. 1C, the point light sources 122 are also It can be arranged in multiple columns, and the point light sources 122 in each column are arranged in a staggered manner. The point light source 122 can be a single-point light-emitting element such as a light-emitting diode or a small light bulb, and is used to project a scanning light S toward the reflective surface 112 . After the scanning light S passes through the slit 111 , it is projected on the surface of the document D to be scanned, and then the scanning light S is reflected by the document D according to the image form of the surface of the document D to form an image light I, and then enters the housing 110 through the slit 111 .

The reflector 130 is disposed in the casing 110 for reflecting the image light I to change the traveling direction of the image light I, so that the image light I advances toward the image sensing element 150 . In addition to changing the traveling direction of the image light I, another function of the mirror 130 is to extend the optical path length of the image light I, so that the image light I can be focused. The number of mirrors 130 can be one or more, and the number is determined by the number of times the image light I needs to change directions and the length of the optical path. At least one mirror 130 is arranged below the slit 111 to allow the image light I to pass through the slit. 111 can then be incident on the mirror 130 and be reflected.

The focusing element 140 and the image sensing element 150 are arranged in the casing 110 to receive the image light I reflected by the document D, wherein the positions of the focusing element 140 and the image sensing element 150 depend on the size of the internal space of the casing 110 and the reflection The configuration of the mirror 130 is determined. The focusing element 140 can be a convex lens, a lenticular lens, or a combination of multiple lenses. It is arranged in front of the image sensing element 150, so that the image light I is incident on the focusing element 140 and is focused on the image sensing element by the focusing element 140. The element 150 enables the image sensing element 150 to convert the image light I into image data after receiving the focused image light I. The image sensing element 150 can be arranged at any position inside the casing 110 to match the optical path of the image light I, wherein the image sensing element 150 is a Charge Coupled Device (CCD), so the image light requires a long optical path to focus. The charge-coupled device can also be replaced by a contact image sensor (Contact Image Sensor, CIS) to save the focusing procedure and the long optical path required for focusing, that is, the mirror 130 and the focusing device 140 are omitted.

Please refer to FIG. 2 and FIG. 3 again, which are schematic diagrams of a plurality of point light sources 122 arranged at intervals to emit light and a schematic diagram of light intensity distribution. The light emitted by the point light source 122 is distributed along a conical space, and the light intensity decreases with distance. The area between two adjacent point light sources 122 can only rely on the scattering effect of the air to generate weak luminous flux. Therefore, if multiple point light sources 122 are used to directly project the scanning light S onto the document D, the received light intensity on the surface of the document will be inconsistent, showing a sinusoidal distribution, resulting in inconsistencies in the quality of the image data converted by the image sensing element, such as Figure 3 shows a schematic diagram of the light intensity distribution. This phenomenon can be achieved by lengthening the distance between the point light sources 122 and the document, or increasing the number of point light sources 122 and reducing the distance between the point light sources 122, so that the scanning light S emitted by each point light source 122 appears in an interlaced area, so as to Evens out the light intensity distribution. But elongating the distance between the point light source 122 and the document will make the average light intensity of the scanning light S decrease, and increase the volume of the scanning device; and increasing the number of point light sources 122 and reducing the distance between the point light sources 122 will make the consumption The power increases, and the high heat of the point light source 122 will also cause heat dissipation problems.

Referring to Fig. 4 and Fig. 5 again, in the first embodiment of the present utility model, after using the reflective surface 112 to reflect the scanning light S emitted by the point light source 122, the scanning light S emitted by each point light source 122 is interlaced and passed through The diffusion and scattering effect produces a mixing effect, so that the scanning light S reflected by the reflective surface 112 forms a line light source and has a uniform light intensity distribution, as shown in FIG. 5 . Regardless of whether the point light source 122 is in the form of a light-emitting diode or a small light bulb, compared with the conventional cold-cathode tube, it has the advantages of low power consumption, low operating voltage, fast startup, and low manufacturing cost. The performance of the new type in start-up time, manufacturing cost and power consumption is better than that of a scanning device using a cold-cathode tube as a scanning light source.

Referring to FIG. 6 , the first embodiment of the present invention is applied to a paper-fed scanner 200. This paper-fed scanner 200 has at least one body 210 and a paper-feeding device 220, wherein the scanning device 100 is set In the body 210 and below a window 211 of the body 210 , the slit 111 of the housing 110 corresponds to the window 211 of the body 210 , and the window 211 is covered by a transparent partition 212 . A paper track 221 is formed inside the paper feeding device 220 for the document D to be transported on the paper track 221 . The paper feeding device 220 is disposed on the main body 210 and covers the window 211 . An opening 222 is defined on a side of the paper feeding device 220 facing the main body 210 to expose the paper track 221 , and the opening 222 is covered by an auxiliary transparent partition 223 . The opening 222 overlaps and corresponds to the window 211, so that when the document D advances on the paper track 221 and passes above the window 211, the scanning light S emitted by the point light source 122 of the scanning device 100 passes through the slit 111 and passes through the transparent The spacer 212 and the auxiliary transparent spacer 223 then fall on the document D through the opening 222 and are reflected to form the image light I. The image light I enters the scanning device 100 to be converted into image data by the image sensor 150 .

Referring to FIG. 7 , the first embodiment of the present invention is applied to a flatbed scanner 300. This flatbed scanner 300 has at least one body 310 and a mobile device 320, wherein the scanning device 100 is arranged on the body 310 and located below a transparent partition 311 of the body 310 , so that the slit 111 of the housing 110 faces the transparent partition 311 of the body 310 . The moving device 320 is disposed in the main body 310 to move the scanning device 100 relative to the main body 310 so as to scan a document image flatly attached to the transparent partition 311 through the transparent partition 311 and convert it into image data.

Please refer to FIG. 8A and FIG. 8B, which is a scanning device 100 disclosed in the second embodiment of the present invention, which includes a housing 110, two reflecting surfaces 112, two light emitting units 120, and one or more reflecting mirrors 130. , a focusing element 140 , and an image sensing element 150 . A slit 111 is defined on the top surface of the housing 110 for light to pass through. The two reflective surfaces 112 are disposed in the housing 110 and respectively extend on the two side edges of the slit 111, and the two reflective surfaces 112 are respectively facing the slit 111 for allowing light to enter the reflective surface 112 and reflect the light through The slit 111 is projected toward the outside of the casing 110 .

8A and 8B, each light-emitting unit 120 includes a substrate 121 and a plurality of point light sources 122, wherein the two substrates 121 are respectively arranged on the corresponding side edges of the two reflective surfaces 112, so that the two substrates are respectively located on the two sides of the slit 111. side edge. A plurality of point light sources 122 are fixed on the substrate 121, and arranged in a row or in multiple rows at intervals along the direction parallel to the slit 111, for projecting a scanning light S toward the reflective surface 112, and the scanning light S passes through after being reflected. The slit 111 projects toward the outside of the housing 110 . After the scanning light S passes through the slit 111 , it is projected on the surface of the document D to be scanned, and then is reflected according to the image form of the surface of the document D to form an image light I, and then enters the casing 110 through the slit 111 . The reflector 130 is disposed in the casing 110, and is used for reflecting the image light I to change the traveling route of the image light I, so that the image light I travels toward the image sensing element 150. The focusing element 140 and the image sensing element 150 are arranged in the casing 110, the focusing element 140 is located in front of the image sensing element 150, after the image light I is incident on the focusing element 140, it is focused on the image sensing element 150 by the focusing element 140, After the image sensing element 150 receives the focused image light I, it is converted into image data.

Please refer to FIG. 9A, FIG. 9B and FIG. 9C, which is a scanning device 100 disclosed in the third embodiment of the present invention, which includes a housing 110, a reflective surface 112, a light emitting unit 120 and an image sensor Element 150'. A slit 111 is defined on the top surface of the housing 110 for light to pass through. The reflective surface 112 is disposed in the housing 110 and extends on one side edge of the slit 111, and the reflective surface 112 faces the slit for allowing light to enter the reflective surface 112 and reflect the light through the slit 111 to the housing. Body 110 projects externally.

The light-emitting unit 120 includes a substrate 121 and a plurality of point light sources 122, the substrate 121 is fixed on a corresponding side edge of the reflective surface 112, and the plurality of point light sources 122 are fixed on the substrate 121 and arranged at intervals along a direction parallel to the slit 111 In multiple rows, as shown in FIG. 9B and FIG. 9C , and the point light sources 122 in each row are arranged in a staggered manner. Likewise, the point light sources 122 can also be arranged in a row. The point light source 122 is used for projecting a scanning light S toward the reflective surface 112 , and the scanning light S is reflected and projected toward the outside of the casing 110 through the slit 111 . After the scanning light S passes through the slit 111 , it is projected on the surface of the document D to be scanned, and then is reflected according to the image form of the surface of the document D to form an image light I, and then enters the casing 110 through the slit 111 . The image sensing element 150' is a contact-type image sensing element, which can directly receive the image light I and convert it into image data, and the optical path length required by the contact-type image sensing element is smaller than that of the charge-coupled element, so the image sensing element 150 ′ can be disposed in the housing 110 and below the slit 111 , and directly receives the image light I reflected by the document D and converts it into image data. However, it is worth noting that the third embodiment of the present invention can also have two reflective surfaces 112 and two light emitting units 120, and the two reflective surfaces 112 are respectively facing the slit 111 for allowing light to enter the reflective surface 112. The light is reflected through the slit 111 and projected to the outside of the casing 110 .

By adopting the utility model, the light intensity of the light emitted by point light sources such as light-emitting diodes can be effectively made uniform without adding additional components. The linear light source of the cold cathode tube is replaced by a plurality of point light sources, which effectively reduces the problems of high manufacturing cost and difficult operation of the cold cathode tube.

Of course, the utility model can also have other various embodiments, without departing from the spirit and essence of the utility model, those of ordinary skill in the art can make various corresponding changes and deformations according to the utility model , but these corresponding changes and deformations should all belong to the scope of protection of the appended claims of the present utility model.

Claims (13)

1. a scanning means in order to scan the image of a file, is characterized in that, this scanning means includes:

One housing, its end face are offered a slit;

At least one reflecting surface, it is arranged in the housing, and extends a lateral edges of this slit, and towards this slit;

At least one luminescence unit, it comprises

One substrate is fixed in a lateral edges of this reflecting surface; And

A plurality of point-source of lights, be fixed on this substrate, and be spaced along the direction that is parallel to this slit, respectively this point-source of light is in order to throw one scan light towards this reflecting surface, this scan light is reflected is projeced into this document surface by this slit afterwards, this scan light is reflected to form an image light by this document, enters in this housing by this slit again; And

One Image Sensor is arranged in this housing, is converted to an image data in order to receive by this image light that this document reflected.

2. scanning means according to claim 1, it is characterized in that, this housing has two reflectings surface, extend the dual side-edge edge of this slit respectively and towards this slit, and this scanning means has two luminescence units, be arranged at the respective side edge of this two reflecting surface respectively, respectively towards this reflecting surface projection one scan light respectively.

3. scanning means according to claim 1 is characterized in that the surface of this reflecting surface forms a reflector.

4. scanning means according to claim 1 is characterized in that, this reflecting surface is a plane or a concave curved surface.

5. scanning means according to claim 1 is characterized in that, respectively this point-source of light is light-emitting diode or bulb.

6. scanning means according to claim 1 is characterized in that, also comprises a concentrating element, be arranged in this housing, and be positioned at this Image Sensor the place ahead, with so that this image light be focused in this Image Sensor.

7. scanning means according to claim 1, it is characterized in that, also comprise at least one speculum, be arranged in this housing, change the direct of travel of this image light in order to reflect this image light, make this image light advance and prolong the optical path length that this image light is advanced towards this Image Sensor.

8. scanning means according to claim 7 is characterized in that, this Image Sensor is a charge coupled cell.

9. scanning means according to claim 1 is characterized in that, this Image Sensor is a contact-type Image Sensor.

10. scanning means according to claim 9 is characterized in that, this contact-type Image Sensor can be arranged in this housing and be positioned at this slit below, directly receives this image light that is reflected by this document, and is converted to image data.

11. scanning means according to claim 1 is characterized in that, this point-source of light is spaced into row along the direction that is parallel to this slit.

12. scanning means according to claim 1 is characterized in that, this point-source of light is spaced into multiple row along the direction that is parallel to this slit.

13. scanning means according to claim 12 is characterized in that, this point-source of light of each row is staggered.

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