File scanning device with dynamic adjustment function

Abstract

The invention provides a file scanning device with a dynamic adjustment function. The file scanning device comprises a file detector, a penetrating light source, an image sensor and a controller. The file detector is used for detecting the penetration rate of a file so as to output a penetration rate signal. The penetrating light source outputs original penetrating light, and the original penetrating light penetrates a file to become penetrating light to be measured. The image sensor receives the penetrating light to be detected so as to generate an image signal. The controller is electrically connected to the file detector, the penetrating light source and the image sensor, wherein the controller controls the penetrating light source to output the luminous quantity of the original penetrating light according to the penetrating rate signal. Through the file scanning device, penetrating light sources with different luminous quantities can be provided for scanning according to files with different penetrating rates.

Description

Technical Field

[0001] The invention relates to a document scanning device, and in particular to a document scanning device with a dynamic adjustment function. Background Art

[0002] When performing scanning, the feed-type document scanner of the prior art requires a document detector to detect when the document passes a certain point, and then starts to collect the image of the document at a predetermined time point. The document detector includes a contact detector and a non-contact detector. The contact detector uses the principle of a lever to allow the document to push the arm of the detector to rotate and trigger a switch. The non-contact detector uses the principle of reflection or penetration to detect whether the document exists.

[0003] On the other hand, the current document scanner defines the document edge by user settings or predetermined size settings, so it is not possible to accurately define the document edge. Therefore, how to use a document detector to detect the existence of a document and the transparency of a document so as to dynamically adjust the light intensity of the penetrating light source of the document scanning device to help define the edge, hole or outline of the document is a problem that the present invention intends to solve. Summary of the invention

[0004] An object of the present invention is to provide a document scanning device with a dynamic adjustment function.

[0005] To achieve the above object, the present invention provides a document scanning device with dynamic adjustment function, comprising a document detector, a penetrating light source, an image sensor and a controller. The document detector is used to detect the transmittance of the document, thereby outputting a transmittance signal. The penetrating light source outputs original penetrating light, which penetrates the document and becomes the penetrating light to be measured. The image sensor receives the penetrating light to be measured and generates an image signal. The controller is electrically connected to the document detector, the penetrating light source and the image sensor, wherein the controller controls the light emission of the original penetrating light output by the penetrating light source according to the transmittance signal.

[0006] Through the document scanning device of the above embodiment, the document detector can be used to detect the existence of the document and the penetration of the document to dynamically adjust the light emission of the penetrating light source of the scanning module, so that the scanning result of the penetrating light image of the document can be optimized, thereby making it easier to process. In addition, the dynamic adjustment can be performed on a document-by-document basis, or can be performed continuously or section-by-section.

[0007] In order to make the above contents of the present invention more clearly understood, preferred embodiments are specifically cited below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 A schematic diagram of the structure of a document scanning device according to a preferred embodiment of the present invention;

[0009] Figure 2 A flowchart of a document scanning device implementing dynamic adjustment according to an embodiment of the present invention;

[0010] Figure 3 A circuit diagram for dynamically adjusting a document scanning device according to an embodiment of the present invention;

[0011] Figure 4 A schematic diagram of detection results of an exemplary embodiment of dynamic adjustment implemented by a document scanning device according to an embodiment of the present invention;

[0012] Figure 5 for Figure 1 A schematic structural diagram of a modified embodiment of the present invention.

[0013] Description of reference numerals:

[0014] C, capacitor; D, file; D1, photodiode; D2, photodiode; DGND, digital ground terminal; IR_ADC, analog voltage signal; IR_PWM, PWM signal; L1, original transmitted light; L1', second original transmitted light; L2, transmitted light to be measured; L2', second transmitted light to be measured; L3, first transmitted light; L4, first light to be measured; L5, second transmitted light; L6, second light to be measured; P, photo; Q, transistor; R1, resistor; R2, resistor; S1, transmittance signal; S11, first sub-signal; S12, second sub-signal; S2, image signal; S2', second image signal; S3, visible light signal; S31~S36, steps;

[0015] 10. Document detector; 11. Light transmitter; 12. Light receiver; 13. First light transceiver; 14. Second light transceiver; 20. Transmitting light source; 20'. Second transmitting light source; 30. Image sensor; 30'. Second image sensor; 40. Controller; 41. ASIC; 42. Current control unit; 50. Visible light source; 60. Feed roller; 70, 70'. Scanning module; 100. Document scanning device. DETAILED DESCRIPTION

[0016] Figure 1 FIG. 1 is a schematic diagram of the structure of a document scanning device according to a preferred embodiment of the present invention. Figure 1 As shown, a document scanning device 100 with dynamic adjustment function includes a document detector 10, a penetrating light source 20, an image sensor 30 and a controller 40. In this embodiment, the document scanning device 100 is described by taking a feed-type scanner as an example, wherein a feed roller 60 feeds a document D through scanning modules 70 and 70'. The following description takes two scanning modules as an example, but the present invention is not limited thereto, because a single scanning module is also applicable.

[0017] The document detector 10 is used to detect the penetration of the document D and output a penetration signal S1. The following description uses thickness as the penetration and thickness signal as the penetration signal S1, but the present invention is not limited to this because the material of the document will also affect the penetration. Based on the existing document detector 10, adding a light control suitable for the detection of the penetration to provide a reference basis for the penetration can achieve the function of dynamically adjusting the penetrating light source of the scanning module. In one embodiment, the document detector 10 continuously detects to detect the time point when the document D begins to exist and disappears, which can be used as a reference for the starting time point of the scanning module to collect images. In another embodiment, when the document detector 10 detects the existence of a document, it starts intermittent detection for a period of time and then continues to detect to reduce power consumption and the amount of data collected.

[0018] The penetrating light source 20 of the scanning module 70' outputs the original penetrating light L1. The original penetrating light L1 penetrates the document D and becomes the penetrating light L2 to be measured. In one embodiment, infrared light is used as the original penetrating light L1.

[0019] The image sensor 30 of the scanning module 70 receives the penetrating light L2 to generate an image signal S2. The image sensor 30 is, for example, a charge-coupled device (CCD) type image sensor or a contact image sensor (CIS), which cooperates with a lens module (not shown) to perform optical sensing.

[0020] The controller 40 is electrically connected to the document detector 10, the penetrating light source 20 and the image sensor 30. The penetrating light source 20 is a linear light source, such as a combination of an infrared light source and a light guide rod. The controller 40 controls the luminous intensity of the original penetrating light L1 output by the penetrating light source 20 according to the transmittance signal S1, which can be controlled by voltage, current and luminous time. In one embodiment, the luminous intensity represents the luminous intensity of continuous luminescence. In another embodiment, the luminous intensity represents the luminous period of intermittent luminescence, such as the duty cycle of pulse width modulation, which is equivalent to the luminous energy per unit time.

[0021] The document scanning device 100 may further include a second penetrating light source 20' and a second image sensor 30'. The second penetrating light source 20' of the scanning module 70 outputs a second original penetrating light L1'. The second original penetrating light L1' penetrates the document D and becomes a second penetrating light to be measured L2'. The second image sensor 30' of the scanning module 70' receives the second penetrating light to be measured L2' and generates a second image signal S2'. The controller 40 is electrically connected to the scanning modules 70 and 70'. Therefore, the controller 40 is also electrically connected to the second penetrating light source 20' and the second image sensor 30'. Through this embodiment, the controller 40 can also control the light emission amount of the second original penetrating light L1' output by the second penetrating light source 20' according to the transmittance signal S1.

[0022] The document detector 10 includes a light emitter 11 and a light receiver 12. The light emitter 11 emits a first penetrating light L3, which penetrates the document D and becomes a first light to be measured L4. The light receiver 12 receives the first light to be measured L4 and generates a transmittance signal S1, wherein the light emitter 11 and the light receiver 12 are disposed on opposite sides of the document D.

[0023] However, it is understandable that, in another example, the document scanning device 100 may also be a flatbed scanner, wherein a driving mechanism (not shown) drives the scanning modules 70, 70' and the document detector 10 to move, and in terms of the moving direction, the document detector 10 is located upstream of the scanning modules 70, 70'.

[0024] In addition, the document scanning device 100 may further include a visible light source 50, wherein the visible light emitted by the visible light source 50 is reflected by the document D and reaches the image sensor 30, so that the image sensor 30 also generates a visible light signal S3. The controller 40 can define the outline of the document D according to the visible light signal S3 and the image signal S2 to achieve a precise border cutting effect.

[0025] It is understandable that a photo P may be attached to the document D, and the document D may have multiple sections with different thicknesses or transmittances. In this case, the document detector 10 can detect the different thicknesses or transmittances of the multiple sections of the document D and output the transmittance signal S1, so that the controller 40 can control the transmission light source 20 to output different amounts of original transmission light L1 to the document D to meet the scanning requirements of sections with different thicknesses or transmittances.

[0026] Figure 2 The present invention is a flowchart of a document scanning device implementing dynamic adjustment. Figure 3 The circuit diagram for implementing dynamic adjustment is shown in FIG. Figures 1 to 3As shown, in step S31, the controller 40 uses a pulse width modulation (PWM) method to cooperate with the capacitor C, the resistor R1 and the transistor Q to output a PWM signal IR_PWM to control the photodiode D1 (one end of which is coupled to the digital ground terminal DGND) of the document detector 10 to output the first transmitted light L3, and in step S32, the photodiode D2 of the document detector 10 is controlled to cooperate with the resistor R2 to receive the first light to be detected L4 to generate an analog voltage signal IR_ADC. Then, in step S33, the analog-to-digital converter (ADC) of the application specific integrated circuit (ASIC) 41 of the controller 40 converts the analog voltage signal into a digital signal, and the ASIC 41 converts the digital signal into a transmittance signal S1 representing the thickness or transmittance of the document D, and also determines whether the transmittance signal S1 is greater than a predetermined level. In one embodiment, the predetermined level may correspond to the specification of the file D. The controller 40 may determine whether the specification of the file D is greater than, for example, 80 gsm (grams per square meter, Grams / Square Meter) based on the transmittance signal S1 and the data in the database, that is, whether the thickness of the file is greater than the thickness corresponding to 80 gsm paper, for example, in the range of 0.063 mm to 0.073 mm.

[0027] If the transmittance signal S1 is greater than the predetermined level, the process proceeds to step S34, where the current control unit 42 of the controller 40 controls the penetrating light source 20 to output the original penetrating light L1 with a first current (e.g., a high current). If the transmittance signal S1 is not greater than the predetermined level, the process proceeds to step S35, where the current control unit 42 of the controller 40 controls the penetrating light source 20 to output the original penetrating light L1 with a second current (e.g., a low current), where the second current is lower than the first current. Next, in step S36, the scanning module starts the image acquisition operation of the image scanning. This control method provides a simple classification method, because general documents can obtain good results based on this classification method, so that the image sensor 30 senses the sensing result of the penetrating light, and the controller 40 can perform simple processing to obtain the contour corresponding to the document D, so as to be combined with the reflected light sensing result described below to achieve the effect of accurate boundary cutting or hole definition.

[0028] The above embodiment is only an example of two-stage control of the penetrating light source 20, but the present invention is not limited thereto. In another embodiment, the controller 40 can control the penetrating light source 20 to output the original penetrating light L1 in a multi-stage current control manner according to the level of the transmittance signal S1. According to the above multi-stage classification method, it can be applied to contour detection of more types of documents.

[0029] It is understandable that the controller can also perform calibration based on a standard document with known thickness and adjust the duty cycle of the PWM signal of step S31 based on the obtained transmittance signal S1 to prevent the document detector 10 from being aged or dirty and affecting the sensing result and subsequent processing procedures.

[0030] Figure 4 FIG. 1 is a schematic diagram of detection results of an exemplary embodiment of dynamic adjustment implemented by a file scanning device according to an embodiment of the present invention. Figure 4 As shown, the PWM control method is to detect five sheets of paper of different thickness (not arranged in order of thickness) at a current of 61 mA and a duty cycle of 67%. The analog voltage signal is sent to the controller's ASIC for sample analysis to distinguish the thickness of the paper (corresponding to the poundage), and the following can be obtained: Figure 4 As shown in the results, this structure allows ASIC to dynamically adjust the brightness of the penetrating light source used to scan documents to obtain optimized results for subsequent image processing.

[0031] Figure 5 for Figure 1 Schematic diagram of a modified embodiment. Figure 5 As shown, this variant embodiment is similar to Figure 1 , the difference is that the document detector 10 includes a first optical transceiver 13 and a second optical transceiver 14, which are disposed on opposite sides of the document D. The first optical transceiver 13 emits a first penetrating light L3, which penetrates the document D and becomes a first light to be measured L4. The second optical transceiver 14 emits a second penetrating light L5, which penetrates the document D and becomes a second light to be measured L6. The first optical transceiver 13 receives the second light to be measured L6 and generates a first sub-signal S11. The second optical transceiver 14 receives the first light to be measured L4 and generates a second sub-signal S12. Therefore, the above-mentioned transmittance signal S1 includes a first sub-signal S11 and a second sub-signal S12.

[0032] In one embodiment, the controller 40 uses the average level represented by the first sub-signal S11 and the second sub-signal S12 to control the transmissive light source 20 .

[0033] In another embodiment, the controller 40 controls the penetrating light source 20 and another penetrating light source according to the first sub-signal S11 and the second sub-signal S12, respectively. In this case, the second penetrating light source 20' outputs the second original penetrating light L1', and the second original penetrating light L1' penetrates the document D and becomes the second penetrating light to be measured L2'. The second image sensor 30' receives the second penetrating light to be measured L2' to generate a second image signal S2'. Therefore, the controller 40 controls the penetrating light source 20 to output the luminous amount of the original penetrating light L1 according to the second sub-signal S12. On the other hand, the controller 40 controls the second penetrating light source 20' to output the luminous amount of the second original penetrating light L1' according to the first sub-signal S11. Through this embodiment, the requirement that the penetrating light presents different penetrabilities in different thickness directions of the document D can be met. For example, one side of the document D is a smooth surface, and the other side is a rough surface, so two standards are used to scan both sides of the document, and a better effect can be obtained.

[0034] Through the document scanning device of the above embodiment, the document detector can be used to detect the existence of the document and the transparency of the document to dynamically adjust the light emission of the penetrating light source of the scanning module, so that the scanning result of the penetrating light image of the document can be optimized and easier to process. In addition, the dynamic adjustment can be performed on a document-by-document basis, or can be performed continuously or section-by-section.

[0035] It is worth noting that all the above embodiments can be appropriately interactively combined, replaced or modified to provide diverse effects.

[0036] The specific embodiments proposed in the detailed description of the preferred embodiments are only used to facilitate the explanation of the technical content of the present invention, rather than narrowly limiting the present invention to the above embodiments. Various changes and implementations made without exceeding the spirit of the present invention and the scope of the patent application are all within the scope of the present invention.

Claims

1. A document scanning device with dynamic adjustment function, characterized in that: Include: A file detector, used to detect the penetration rate of a file and output a penetration rate signal; A penetrating light source, located downstream of the document detector, outputs original penetrating light, and the original penetrating light penetrates the document to become the penetrating light to be detected; An image sensor, located downstream of the document detector, receives the penetrating light to be detected and generates an image signal; as well as A controller is electrically connected to the document detector, the penetrating light source and the image sensor, wherein the controller controls the penetrating light source to output the luminous amount of the original penetrating light according to the transmittance signal to help define the edge, hole or outline of the document.

2. The document scanning device according to claim 1, wherein: Also includes: a second penetrating light source, outputting a second original penetrating light, wherein the second original penetrating light penetrates the document to become a second penetrating light to be measured; and The second image sensor receives the second penetrating light to be measured to generate a second image signal, wherein the controller is also electrically connected to the second penetrating light source and the second image sensor, and wherein the controller also controls the second penetrating light source to output the luminous intensity of the second original penetrating light according to the transmittance signal.

3. The document scanning device according to claim 1, wherein: The file detector includes: A light emitter, emitting a first penetrating light, wherein the first penetrating light penetrates the document and becomes a first light to be measured; and The light receiver receives the first light to be measured to generate the transmittance signal, wherein the light emitter and the light receiver are disposed on opposite sides of the document.

4. The document scanning device according to claim 3, characterized in that: The controller controls the document detector to output the first penetrating light in a pulse width modulation manner, and controls the document detector to receive the first light to be detected to generate an analog voltage signal. The controller converts the analog voltage signal into the transmittance signal representing the transmittance of the document.

5. The document scanning device according to claim 4, characterized in that: The controller also determines whether the transmittance signal is greater than a predetermined level; if the transmittance signal is greater than the predetermined level, the controller controls the penetrating light source to output the original penetrating light with a first current; if the transmittance signal is not greater than the predetermined level, the controller controls the penetrating light source to output the original penetrating light with a second current, wherein the second current is lower than the first current.

6. The document scanning device according to claim 1, wherein: It also includes a visible light source, wherein the document reflects the visible light emitted by the visible light source to reach the image sensor, so that the image sensor also generates a visible light signal.

7. The document scanning device according to claim 1, wherein: The file detector includes: A first optical transceiver emits a first penetrating light, wherein the first penetrating light penetrates the document to become a first light to be measured; and The second optical transceiver emits a second penetrating light, and the second penetrating light penetrates the document and becomes a second light to be measured, wherein the first optical transceiver receives the second light to be measured and generates a first sub-signal, and the second optical transceiver receives the first light to be measured and generates a second sub-signal, and the transmittance signal includes the first sub-signal and the second sub-signal, wherein the first optical transceiver and the second optical transceiver are arranged on opposite sides of the document.

8. The document scanning device according to claim 7, characterized in that: The controller uses the average level represented by the first sub-signal and the second sub-signal to control the penetrating light source.

9. The document scanning device according to claim 7, characterized in that: Also includes: a second penetrating light source, outputting a second original penetrating light, wherein the second original penetrating light penetrates the document to become a second penetrating light to be measured; and a second image sensor, receiving the second penetrating light to be measured and generating a second image signal, wherein the controller is also electrically connected to the second penetrating light source and the second image sensor, wherein: The controller controls the penetrating light source to output the luminous intensity of the original penetrating light according to the second sub-signal; and The controller controls the second penetrating light source to output a light amount of the second original penetrating light according to the first sub-signal.

10. The document scanning device according to claim 1, wherein: The document detector detects different transmittances of multiple sections of the document and outputs the transmittance signal, so that the original transmitted light outputs different luminous amounts to the document.

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