Disclosure of Invention
It is an object of the present invention to provide a photosensitive device with an inclined background sheet for providing automatic trimming and skew correction functions.
To achieve the above objective, the present invention provides a photosensitive device, which includes a paper feeding path, a first photosensitive assembly and a first background sheet. The paper feeding channel is provided with a scanning window. The first photosensitive assembly is arranged on the first side of the scanning window and emits first scanning light towards the scanning window. The first background sheet is arranged on the second side of the scanning window and is provided with a first reflecting surface, and the first reflecting surface reflects the first scanning light passing through the scanning window to pass through the scanning window and return to the first photosensitive assembly. The first reflecting surface of the first background sheet is arranged in a non-parallel way with the scanning window.
The photosensitive device can further comprise a second photosensitive assembly and a second background sheet. The second photosensitive assembly is arranged on the second side of the scanning window and emits a second scanning light towards the scanning window. The second background sheet is arranged on the first side of the scanning window and is provided with a second reflecting surface, and the second reflecting surface reflects the second scanning light passing through the scanning window to pass through the scanning window and return to the second photosensitive assembly. The second reflecting surface of the second background sheet is arranged in a non-parallel way with the scanning window.
In the above-mentioned photosensitive device, when the data medium is fed through the scanning window along the paper feeding path by the feeding mechanism of the photosensitive device, a first portion of the first scanning light is reflected by the first surface of the data medium back to the first photosensitive element to generate a first scanning signal, and a second portion of the first scanning light is reflected by the first background sheet back to the first photosensitive element to generate a first background signal.
The invention also provides a photosensitive method, which is applied to the photosensitive equipment and comprises the following steps: feeding a data medium into a paper feeding channel; generating a mixed signal of a first scanning signal and a first background signal according to the following steps: before the data medium passes through the scanning window, the first photosensitive assembly senses a second part of the first scanning light; when the data medium passes through the scanning window, the first photosensitive assembly senses a first part and a second part of the first scanning light; after the data medium passes through the scanning window, the first photosensitive assembly senses a first part of the first scanning light; and separating the first scanning signal from the mixed signal according to the characteristic of the first background signal.
By the photosensitive equipment, the inclined background sheet can be used for providing a gray-scale background which is different from a white background of a data medium, and the functions of automatic cutting and skew correction are achieved. Furthermore, the driving mechanism can drive the background piece to rotate to the horizontal state so as to provide the effect of brightness correction. In addition, the driving mechanism can drive the background piece to rotate to other inclined angles so as to provide background effects with different gray scales. The characteristic can be completed by using a single background sheet, the structure is simple, the effect is obvious, and an effective background detection effect can be provided for the paper-fed scanner.
In order to make the aforementioned and other objects of the present invention comprehensible, preferred embodiments accompanied with figures are described in detail below.
Drawings
The following description will explain embodiments of the present invention in further detail with reference to the accompanying drawings.
FIGS. 1 and 2 are schematic views showing two states of a photosensitive device according to a preferred embodiment of the invention;
FIG. 3 is a schematic view of a light emitting device and a sensing device;
FIGS. 4A and 4B show an example of optical path diagrams corresponding to FIGS. 1 and 2, respectively;
FIGS. 5A and 5B show another example of optical path diagrams corresponding to FIGS. 1 and 2, respectively;
FIG. 6 shows a schematic diagram of automatic cropping;
FIG. 7 is a schematic diagram illustrating skew correction;
FIG. 8 is a flowchart illustrating a photosensitive method according to a preferred embodiment of the invention.
Element number description:
a: size of
A1: first angle
A2: second angle
B: size of
BD: boundary of
IB: image forming method
IM: image forming method
L1: first scanning ray
L2: second scanning light
M: data medium
M1: first side
M2: second surface
R1, R2, R3: reflected light
S1: first scanning signal
S2: first background signal
S3: second scanning signal
S4: second background signal
S5: first correction signal
S6: second correction signal
ST1 to ST 3: step (ii) of
1: photosensitive device
3: feeding mechanism
3A, 3B, 3C, 3D: feed roller
10: paper feeding channel
11: scanning window
20: first photosensitive assembly
21: first light emitting assembly
21A: light source
21B: light guide column
22: first induction assembly
22A: lens array
22B: sensing element array
30: first background sheet
30A: first reflecting surface
40: first light-transmitting substrate
50: second light-transmitting substrate
60: second photosensitive assembly
61: second light emitting component
61A: light source
61B: light guide column
62: second induction assembly
62A: lens array
62B: sensing element array
70: second background sheet
70A: second reflecting surface
80: first driving mechanism
85: second driving mechanism
90: processor with a memory having a plurality of memory cells
Detailed Description
The following description of the embodiments of the present invention is provided for illustrative purposes, and other advantages and effects of the present invention will become apparent to those skilled in the art from the present disclosure. While the invention will be described in conjunction with the preferred embodiments, it is not intended that features of the invention be limited to these embodiments. On the contrary, the invention is described in connection with the embodiments for the purpose of covering alternatives or modifications that may be extended based on the claims of the present invention. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. The invention may be practiced without these particulars. Moreover, some of the specific details have been left out of the description in order to avoid obscuring or obscuring the focus of the present invention.
A linear Image Sensor (line Image Sensor) is composed of a plurality of sensors, which are arranged in a straight line and have consistent pitches, and generate different voltages for the intensity of reflected light, and two products, namely a Charge-coupled device (CCD) type Image Sensor and a Contact Image Sensor (CIS), are commercially available, and especially CIS is widely used in scanners due to its low price. The embodiment of the invention can be applied to the two sensors, and can provide gray-scale background to be distinguished from the white background of the data medium by matching with the inclined background sheet, thereby being beneficial to the execution of subsequent automatic trimming and skew correction.
FIGS. 1 and 2 are schematic diagrams illustrating two states of a photosensitive device according to a preferred embodiment of the invention. As shown in fig. 1 and fig. 2, the photosensitive device 1 of the present embodiment is, for example, a sheet-fed scanner, and captures an image of the data medium while feeding the data medium. Although the drawings are implemented with a double-sided scanner, the present invention is not limited thereto, since a single-sided scanner can also achieve the effects of the present invention. The photosensitive device 1 includes a paper feeding path 10, a first photosensitive assembly 20, and a first background sheet 30. Thus, the effect of single-side scanning can be achieved. To perform the duplex scanning, the photosensitive apparatus 1 may further include a second photosensitive member 60 and a second background sheet 70.
The paper path 10 has a scanning window 11. The first photosensitive element 20 is disposed on a first side of the scanning window 11 and emits a first scanning light L1 toward the scanning window 11. The second photosensitive element 60 is disposed on the second side of the scanning window 11 and emits a second scanning light L2 toward the scanning window 11.
The first background sheet 30 is disposed on the second side of the scanning window 11 and has a first reflective surface 30A for reflecting the first scanning light L1 passing through the scanning window 11 back to the first photosensitive element 20 through the scanning window 11. The second background sheet 70 is disposed on the first side of the scanning window 11 and has a second reflective surface 70A for reflecting the second scanning light L2 passing through the scanning window 11 back to the second photosensitive element 60 through the scanning window 11. The first side and the second side are opposite sides, and are illustrated as an upper side and a lower side in fig. 1. That is, the connecting line of the first background sheet 30 and the first photosensitive member 20 intersects the scanning window 11.
In the present embodiment, the first reflective surface 30A of the first background sheet 30 and the scanning window 11 are disposed in a non-parallel manner, so that the first background sheet 30 provides a gray background to achieve the boundary detection effect. In addition, the second reflective surface 70A of the second background sheet 70 is disposed non-parallel to the scanning window 11, so that the second background sheet 70 provides a gray background to achieve the boundary detection effect. The first reflecting surface 30A reflects the first scanning light L1, and the second reflecting surface 70A reflects the second scanning light L2.
The photosensitive device 1 may further include a first transparent substrate 40 and a second transparent substrate 50 respectively disposed at two sides of the scanning window 11 and located between the first photosensitive element 20 and the first background sheet 30, or located between the second photosensitive element 60 and the second background sheet 70. In the present embodiment, the first transparent substrate 40 and the second transparent substrate 50 are disposed in parallel, and both define the range of the scanning window 11. The first transparent substrate 40 and the second transparent substrate 50 are made of a material selected from the group consisting of glass, Polycarbonate (PC), polypropylene (pp), acrylonitrile-butadiene-Styrene (ABS) resin, and polymethyl methacrylate (PMMA). In the present embodiment, the first background sheet 30 and the second background sheet 70 are both strip sheets, which can reduce the space between the transparent substrate and the photosensitive element. In another embodiment, the first background sheet 30 and the second background sheet 70 can be present in a triangular manner to provide an effect of being conveniently mounted on the transparent substrate or the photosensitive element. It should be noted that the scanning window 11 is not necessarily defined by the first transparent substrate 40 and the second transparent substrate 50, but may be defined by a single transparent substrate, or may be defined by a guiding plate having an opening. In addition, the first transparent substrate 40 and the first reflective surface 30A of the first background sheet 30 are disposed in a non-parallel manner, and the second transparent substrate 50 and the second reflective surface 70A of the second background sheet 70 are disposed in a non-parallel manner.
In the embodiment, the first background piece 30 and the scanning window 11 are disposed at a first angle a1, the second background piece 70 and the scanning window 11 are disposed at a second angle a2, and the first angle a1 is equal to the second angle a 2. In one example, the first angle A1 is between 3 and 30, and the gray scale sensed by the first sensing elements 22 is between 240 and 100 (the pure white gray scale is 255). In another example, the first angle a1 is between 10 and 20 degrees, preferably between 12 and 15 degrees, and the gray scale sensed by the first sensing elements 22 is between 170 and 160. However, in another example, the first angle A1 is not equal to the second angle A2 to provide the appropriate different gray level backgrounds for files with different backgrounds on the front and back.
The first photosensitive element 20 includes a first light emitting element 21 and a plurality of first sensing elements 22. The second photosensitive element 60 includes a second light emitting element 61 and a plurality of second sensing elements 62. The first background sheet 30 is disposed opposite the plurality of first sensing elements 22 and the second background sheet 70 is disposed opposite the plurality of second sensing elements 62. The first light emitting element 21 emits a first scanning light L1 toward the scanning window 11, and the second light emitting element 61 emits a second scanning light L2 toward the scanning window 11. The plurality of first sensing elements 22 receive the first scanning light L1 reflected by the first background sheet 30, and the plurality of second sensing elements 62 receive the second scanning light L2 reflected by the second background sheet 70.
In addition to sensing the gray level of the first background piece 30 and the second background piece 70, the first photosensitive element 20 and the second photosensitive element 60 can also be used for scanning the data medium M. When the data medium M is fed through the scanning window 11 by the feeding mechanism 3 of the photosensitive device 1 along the paper feeding path 10, a first portion of the first scanning light L1 is reflected by the first side M1 of the data medium M back to the first photosensitive element 20 to generate a first scanning signal S1. The second portion of the first scanning light L1 is reflected by the first background sheet 30 back to the first photosensitive element 20 to generate a first background signal S2. The first and second portions of the first scanning light line L1 extend in the direction of the drawing plane, and constitute illumination light in the width direction of the data medium M (substantially perpendicular to the direction of travel of the data medium M, if the plane of fig. 1 is an XY plane, the width direction is the Z-axis direction). The first portion of the second scanning light L2 is reflected by the second side M2 of the data medium M back to the second photosensitive element 60 to generate a second scanning signal S3. The second portion of the second scanning light L2 is reflected by the second background sheet 70 back to the second photosensitive element 60 to generate a second background signal S4. The first and second portions of the second scanning light L2 extend in the direction of the drawing, and constitute illumination light in the width direction of the data medium M. In the present embodiment, the feeding mechanism 3 includes feeding rollers 3A, 3B, 3C, and 3D. The scanning window 11 is disposed between the feeding rollers 3A and 3B and the feeding rollers 3C and 3D, and a first light path from the data medium M to the first sensing element 22 and a second light path from the first background sheet 30 to the first sensing element 22 are substantially perpendicular to the data medium M and the paper feeding path 10.
In order to perform the correction of the standard white, the photosensitive apparatus 1 may further include a first driving mechanism 80 connected to the first background sheet 30; and a second drive mechanism 85 connected to the second background sheet 70. In the scanning mode, the first driving mechanism 80 drives the first reflective surface 30A of the first background sheet 30 to rotate relative to the first photosensitive assembly 20 to be in a non-parallel arrangement with the scanning window 11, and the second driving mechanism 85 drives the second reflective surface 70A of the second background sheet 70 to rotate relative to the second photosensitive assembly 60 to be in a non-parallel arrangement with the scanning window 11, that is, the state shown in fig. 1.
In a calibration mode, the first driving mechanism 80 drives the first background sheet 30 to rotate substantially parallel to the scanning window 11 relative to the first photosensitive element 20, and the first photosensitive element 20 receives the first scanning light L1 to obtain a first calibration signal S5; and the second driving mechanism 85 drives the second background sheet 70 to rotate substantially parallel to the scanning window 11 relative to the second photosensitive element 60, and the second photosensitive element 60 receives the second scanning light L2 to obtain the second correction signal S6, i.e. the state shown in fig. 2. In this way, the processor 90 of the photosensitive device 1 can correct the first scanning signal S1 according to the first correction signal S5 and correct the second scanning signal S3 according to the second correction signal S6.
In other modes, the first driving mechanism 80 can drive the first background sheet 30 to rotate to different angular positions to provide different gray levels of the background, and the same technique can be applied to the second driving mechanism 85 and the second background sheet 70.
It is noted that the view of fig. 1 shows that both the first light path and the second light path are possible because the first background patch 30 is typically designed to be wider (width direction perpendicular to the paper of fig. 1) and the data medium M is likely to be narrower than the first background patch 30, so that the first light path is located inside the data medium M and the second light path is located outside the data medium M.
FIG. 3 is a schematic view of a light emitting device and a sensing device. As shown in fig. 3, the first light emitting assembly 21 includes two light sources 21A (a single light source is also possible) and a light guide 21B, and the light guide 21B homogenizes the light of the light sources 21A and guides the homogenized light to move downwards. In addition, the first sensing elements 22 include a lens array 22A and a sensing element array 22B. Similarly, the second light emitting assembly 61 includes two light sources 61A (or a single light source) and a light guiding column 61B, and the light guiding column 61B homogenizes the light of the light sources 61A and guides the light to move downwards. In addition, the first sensing elements 22 include a lens array 62A and a sensing element array 62B.
Fig. 4A and 4B show an example of the optical path diagrams corresponding to fig. 1 and 2, respectively. As shown in fig. 4A and 4B, the intensity of the reflected light R1 is the highest if the first scanning light L1 emitted by the first light-emitting device 21 follows the law that the incident angle is equal to the reflection angle (refer to the normal N), but because the first background sheet 30 itself is not a mirror surface, there is a diffuse reflection phenomenon such that the intensities of the reflected lights R2 and R3 decrease. Therefore, the intensity of the reflected light received by the first sensing assembly 22 of FIG. 4A (lower than the intensity of the reflected light R3) is less than the intensity of the reflected light received by FIG. 4B (higher than the intensity of the reflected light R3). Therefore, the inclined first background slice 30 can provide a gray-scale background to achieve the boundary detection effect of the scanned image of the data medium.
Fig. 5A and 5B show another example of the optical path diagrams corresponding to fig. 1 and 2, respectively. In another point of view, the length of the energy distribution of the first scanning light L1 of the same divergence angle of the first light-emitting assembly 21 on the inclined first background sheet 30 is dimension a, and the length of the energy distribution on the horizontal first background sheet 30 is dimension B, wherein dimension a is greater than dimension B, so that the inclined first background sheet 30 causes the dispersion of the light source energy, so that the energy of the light received by the first sensing assembly 22 is decreased, that is, the decrease in the sensed brightness.
FIG. 6 shows a schematic diagram of automatic cropping. Fig. 7 shows a schematic diagram of skew correction. As shown in fig. 6 and 7, the scanned image includes an image IM of the data medium M at the inner circle and an image IB (surrounding image IM) of the background at the outer circle, because the gray scale (dark, gray scale such as 160) of the image IB is significantly smaller than the gray scale of the background (bright, gray scale such as 220) of the image IM, the processor 90 can find one or more boundaries BD of the image IM corresponding to the first scanning signal S1 according to the first background signal S2, and the processor 90 finds one or more boundaries BD of the image IM corresponding to the second scanning signal S3 according to the second background signal S4. Thus, the processor 90 can perform automatic trimming and skew correction.
In another example, a fixed background slice may be used, in which case the processor 90 may correct the first scanning signal S1 according to the first background signal S2 and correct the second scanning signal S3 according to the second background signal S4. That is, the gray scale corresponding to the background signal is known, and the calibration can be performed according to the gray scale.
FIG. 8 is a flowchart illustrating a photosensitive method according to a preferred embodiment of the invention. As shown in fig. 8, the present embodiment provides a photosensitive method applied to the above-described photosensitive apparatus 1. The photosensitive method comprises the following steps. First, in step ST1, the data medium M is fed into the paper path 10. Then, a mixed signal of the first scanning signal S1 and the first background signal S2 is generated according to the following steps: (a) before the data medium M reaches the scanning window 11, the first photosensitive element 20 senses the second part of the first scanning light L1; (b) when the data medium M passes through the scanning window 11, the first photosensitive element 20 senses the first portion and the second portion of the first scanning light L1; (c) after the data medium M leaves the scanning window 11, the first photosensitive element 20 senses a first portion of the first scanning light L1. Finally, the first scanning signal is separated from the mixed signal according to the characteristics of the first background signal S2S 1. The characteristic of the first background signal S2 corresponds to the inclination angle of the first background piece 30, i.e. corresponds to the gray level of the first reflective surface 30A of the first background piece 30 sensed by the first sensing element 22. The mixed signal is, for example, a signal corresponding to the whole image of fig. 6 or fig. 7. Thus, the functions of background detection for automatic cutting and skew correction can be achieved.
By the photosensitive equipment and the photosensitive method, the inclined background sheet can be used for providing a gray-scale background which is different from a white background of a data medium, and the functions of automatic cutting and skew correction are achieved. Furthermore, the driving mechanism can drive the background piece to rotate to the horizontal state so as to provide the effect of brightness correction. In addition, the driving mechanism can drive the background piece to rotate to other inclined angles so as to provide background effects with different gray scales. The characteristic can be completed by using a single background sheet, the structure is simple, the effect is obvious, and an effective background detection effect can be provided for the paper-fed scanner.
The detailed description of the preferred embodiments is provided only for the convenience of illustrating the technical contents of the present invention, and the present invention is not limited to the above embodiments in a narrow sense, and various modifications can be made without departing from the spirit of the present invention and the scope of the claims.