CN115086502B - Non-contact scanning device - Google Patents

Abstract

A non-contact scanning device, at least comprising a machine, at least comprising a platform structure for placing a scanning object, a scanning member, which is transversely arranged above the platform structure along a second direction and is used for acquiring an image of the scanning object, the scanning member being configured to be movable above the platform structure along a first direction to acquire the image of the scanning object, the scanning member comprising a plurality of light capturing units which are arranged linearly and are used for acquiring at least a part of the image of the scanning object, wherein, in case that a viewpoint distance exists between adjacent light capturing units, the light capturing units are arranged in such a way that the viewpoint distance tapers in sequence along the center to the edge.

Description

Non-contact scanning device

Technical Field

The invention relates to the field of optical scanning devices, in particular to a non-contact scanning device.

Background

Scanners, particularly optical-based scanners, are used to acquire fine image information of at least one face of an object. In the field of document scanning applications, scanners are used to scan content, typically text or pictorial information, on a paper document. The scanner is provided with at least one imaging system for acquiring images of the scanned object, typically an optical imaging device, such as a high-definition camera, a camera, or the like. To obtain a global high definition image of the scanned object, the imaging system is typically configured to move relative to the surface of the scanned object to obtain a global scan field of view. On a flatbed scanner, the movement is effected on the imaging system, which usually involves moving the track of the camera and driving motors. On sheet fed scanners, the movement is achieved by controlling the movement of the scanned object itself, which may be the use of a scrolling device. In most scanners, ambient light is usually removed to minimize the imaging effects of the environment, and the apparatus is usually configured or deformable to opaque structures, such as a cassette structure or a cover plate structure, while the light source components disposed inside the scanner are components that shine on the paper to enable the camera to capture the reflection of the document.

CN101860648B discloses a large format scanner for scanning data carrier assembly movement and a scanning method thereof, comprising: the scanning device comprises a frame, a scanning element group and a scanning data bracket assembly which are arranged on the frame and are composed of a plurality of surface scanning units, and a computer host for controlling the scanning action of the scanning element group and processing scanned pictures and texts; the scanning device is characterized in that the scanning units of all the surfaces are arranged in a row and fixed on the frame and positioned above or below the scanning data bracket component; also includes a horizontal moving mechanism of the scan data bracket assembly connected with the scan data bracket assembly. The horizontal moving mechanism drives the scanning data bracket assembly to move below the scanning element group, the scanning element group scans the corresponding scanned data one by one according to the region sequence, and the computer host adopts multichannel and multithreading technology to splice the scanned pictures and texts and restore the scanned data. The scanning device has the advantages of large scanning amplitude, high precision, small volume and production cost saving.

However, the scanning device in the prior art has the disadvantages of larger volume, more occupied area, inconvenient installation, poor imaging definition and light interference resistance and lower scanning precision.

Furthermore, there are differences in one aspect due to the understanding of those skilled in the art; on the other hand, since the applicant has studied a lot of documents and patents while making the present invention, the text is not limited to details and contents of all but it is by no means the present invention does not have these prior art features, but the present invention has all the prior art features, and the applicant remains in the background art to which the right of the related prior art is added.

Disclosure of Invention

In view of the shortcomings of the prior art, the present invention provides a non-contact scanning device, which at least comprises a machine, at least comprises a platform structure for placing a scanning object, a scanning member transversely arranged above the platform structure along a second direction and used for acquiring an image of the scanning object, the scanning member is configured to be capable of moving above the platform structure along a first direction to acquire the image of the scanning object, the scanning member comprises a plurality of light capturing units which are arranged linearly and used for acquiring at least a part of the image of the scanning object, wherein the light capturing units are arranged in a manner that the viewpoint distance gradually tapers along the center to the edge when the viewpoint distance exists between adjacent light capturing units.

Preferably, the viewpoint distance is a pitch of adjacent light capturing structures, and the viewpoint distance of the light capturing structure near the center is configured to be larger than the viewpoint distance of the light capturing structure near the edge.

Preferably, in the case of an arrangement in which the light capturing units taper in accordance with a trend of the viewpoint distance from the center to the edge, the field of view overlapping areas of adjacent light capturing units vary in a manner of increasing from the center to the edge, so that the image captured by the scanning member with respect to the scanning object, the cross-correctable areas of the image at the edge position thereof are relatively more.

Preferably, the scanning member further comprises a plurality of light sources arranged in the scanning member in a tapered arrangement from the middle to the outside with the light capturing units in such a way that at least the field of view of each light capturing unit can be illuminated.

Preferably, an area of the scan object illuminated by at least two light sources at the same time at the edge position in the second direction is larger than an illuminated area at the intermediate position, so that the edge of the scan object is captured by the light capturing unit in a state where the illumination condition is relatively good.

Preferably, the scanning members are connected to the machine table by driving arms provided at both ends, respectively, to constitute a state of being suspended above the platform structure.

Preferably, each light capturing unit is correspondingly provided with at least one driver configured to be able to adjust its own position in the third direction, the focal length of each light capturing unit being able to be individually adjusted when the position is adjusted in the third direction.

Preferably, a driving structure is provided in the machine, and the driving structure includes a driving rail and driving arms, the driving rail is provided at both sides of the machine along a first direction, and one ends of at least two driving arms extending along a third direction are movably connected to the driving rail, so that a moving direction of the driving arms is limited in the first direction of the driving rail.

Preferably, at least two drive arms are connected by a cross bar, the drive structure further comprising a drive assembly drivingly connected to the cross bar to drive the drive arms to move in the first direction.

Preferably, a partial pressure assist structure for assisting in flattening the scanning object is provided on the platform structure, which is configured to be able to flatten the scanning object on the platform structure based on generating a negative pressure on the platform structure.

Drawings

Fig. 1 is a schematic arrangement view of a light capturing unit according to a preferred embodiment of the present invention;

FIG. 2 is a schematic view of the apparatus according to a preferred embodiment of the present invention;

FIG. 3 is a schematic view of the internal structure of a scanning head according to a preferred embodiment of the present invention;

FIG. 4 is a schematic view of the lifting structure of the driving arm according to a preferred embodiment of the present invention;

in the figure: 100. a machine table; 110. a platform structure; 200. a driving structure; 210. a drive rail; 220. a driving arm; 300. a scanning member; 310. a light capturing unit; 320. a driver; 400. and a control unit.

Detailed Description

The following is a detailed description with reference to fig. 1 to 3.

The invention provides a non-contact scanning device for scanning paper articles. The device is used for acquiring an image of at least one surface of a scanned object. Preferably, the scanning object is paper, and it is generally understood that the paper has at least two pages with large areas, and the pages can be used for recording information by physically attaching markers. Typically the marker may be ink, carbon powder, pen ink or the like; the information is the content, such as words, pictures, tables, etc., conveyed by the specific arrangement of the markers. The present apparatus is preferably used for scanning a fine image of a page portion of a sheet. The device acquires an image of a scanned object in an optical imaging mode. Optical imaging is a process in which light that is reflected to a certain direction from an object after being emitted or irradiated is collected and restored to a digital image by a photosensitive element. Optical imaging typically has photosensitive elements, optical components, shutters, and the like. The light sensing element, such as CMOS and CCD sensor, can convert the light irradiated onto the lattice of the optical sensor into digital light signal and restore the digital light signal to form image information. The optical member is a member for converging and processing light to the light-sensitive element path, which may be basically constituted as a combination of a lens and a plane mirror, and the light path may be changed to achieve an effect of enlarging, reducing, or changing the depth of field of an image. The shutter member is used for controlling the amount of light entering the photosensitive element for a period of time, and when the shutter member is opened, light can enter the photosensitive element.

In this embodiment, as shown in fig. 2, there is provided an apparatus capable of scanning a large-format page, which includes at least a machine 100, an operation member and a scanning member 300, wherein the machine 100 is used for forming a bottom support for supporting the whole apparatus and for bearing a scanned object, so that it has at least one position capable of flattening a sheet, in this embodiment, a platform structure 110 is used as a carrying member for expanding the scanned object, and the platform structure 110 belongs to the machine 100, which may be generally configured as a planar structure, and which may be generally arranged parallel to the ground, so as to facilitate the scanning operation. Preferably, the platform structure 110 may be disposed on or may itself be formed of one of the planes of the machine 100 that is remote from the ground, such as when the machine 100 is disposed in a generally rectangular parallelepiped configuration, when it is placed on the ground, generally one of the planes will be facing and parallel to the ground, and the opposite side thereof that is remote from the ground may be disposed or may itself be formed as the platform structure 110 described above.

Preferably, in order to provide an auxiliary flattening effect of the scan object placed on the above-mentioned platform structure 110, a wind pressure auxiliary structure for forcibly flattening the edge of the scan object by using pressure caused by the flow of the supplied air is provided at the lower or peripheral side of the platform structure 110. Since the document recording tools such as paper often generate curling, wrinkling, twisting and other phenomena in the aging process, the document recording tools are difficult to be placed flatly only by themselves, and the wind pressure auxiliary structure is introduced in the scheme, acts on the platform structure 110 and can assist the paper to be flattened. Specifically, the wind pressure auxiliary structure at least comprises a wind gap, and a channel or a directional flow direction of the gas is generated through the wind gap. The wind pressure auxiliary structure further comprises an air suction unit which is communicated with the air inlet through an air suction pipeline so as to realize that air flow outside the air inlet directionally flows along the direction in the air inlet by applying negative pressure to the air suction pipeline and the air inlet, based on Bernoulli's law, air around at least one part of the scanning object is rapidly pumped away, the flow rate of the air in the part is accelerated, the pressure of the fluid is reduced, and the pressure of other parts presses the scanning object in the part on the platform structure 110. In one embodiment, the tuyeres are disposed on a panel of the platform structure 110, and may be disposed in a random or spaced-apart order, with a mesh structure disposed between the tuyeres and the panel to promote the coverage area of the suction surface, thereby creating a direction of airflow generally normal to the platform structure 110, in which case the backside of the scanned object is "attracted" directly to the platform structure 110. In another embodiment, the tuyeres are disposed on the peripheral side of the platform structure 110, and may be multi-stage or communicating tuyeres disposed along all edges of the platform structure 110, thereby constituting a gas flow direction substantially parallel to the plane of the platform structure 110, in which case the edge portion of the scan object is differential pressure on the platform structure 110 by the gas pressure generated by the gas flow. In other embodiments, both of the above-described tuyere arrangements exist in the arrangement scheme. The air suction units and the air suction pipes may be disposed inside the machine 100.

Thus, the interior of the machine 100 may be configured or partially configured as a hollow structure, i.e., a portion of the accommodating space is provided, and at least a portion of the space except for the portion of the space for accommodating the suction unit and the suction duct may be used for storing other objects, for example, a storage structure may be provided by providing a storage box or a drawer for storing objects such as paper, tools, etc.

Preferably, another embodiment is provided, in this embodiment, the combination of the air suction unit, the air suction channel and the air port is set in a partition manner, that is, the wind pressure auxiliary structure is set in multiple groups, which can be independently controlled to be turned on or off, and the wind pressure auxiliary structure set in multiple groups can be configured to respectively control the auxiliary flattening conditions of the scanning objects in different partitions on the platform structure 110. For example, a first wind pressure auxiliary structure and a second wind pressure auxiliary structure are arranged, wherein the first wind pressure auxiliary structure is arranged in one area of the platform structure 110, and correspondingly, the second wind pressure auxiliary structure is arranged in the other complementary area of the platform structure 110, for example, the first wind pressure auxiliary structure is arranged in the upper half area of the platform structure 110, the second wind pressure auxiliary structure is arranged in the lower half area of the platform structure 110, and the partition induced draft is advantageous in that auxiliary flattening can be respectively carried out on scanning objects in different areas, especially on scanning objects with larger areas, and compared with auxiliary flattening in a single area, the partition auxiliary flattening can smooth large paper better.

Preferably, a power supply is disposed in the machine 100, and the power supply may be a rechargeable battery or a voltage transformation module capable of directly using electric energy transmitted by external electric power, and the power supply is at least electrically connected to the air suction unit to provide power for the air suction unit.

The driving structure 200 is disposed in the machine 100 and can perform a motion of changing a relative position with respect to the platform structure 110, wherein the driving structure 200 can at least perform a parallel movement with respect to the platform structure 110. Specifically, the drive platform includes a drive rail 210 and a drive arm 220, at least a portion of the drive arm 220 being coupled to the drive rail 210, the drive rail 210 defining a direction of movement of the drive arm 220. A drive assembly is also included that provides motive power to the drive arm 220, and in particular, may provide Y-axis scanning motion power in a T-belt driven stepper motor synchronous drive. For convenience of description, the platform structure 110 is taken as a reference object, and as shown in the coordinate axes in the drawing, the platform structure 110 is generally configured as a rectangular plane structure, the direction indicated by the Y axis is the length direction of the platform structure 110, that is, the arrangement and movement direction of the driving rail 210 and the driving arm 220, which may be referred to as the second direction, and the direction indicated by the X axis is the width direction of the platform structure 110, which may be referred to as the first direction.

The driving arm 220 has at least two ends, the vicinity of one end of which is connected to the driving rail 210, and the other end of which extends upward in a direction substantially perpendicular to the ground, i.e., in the Z-axis direction in the drawing, and at least beyond the horizontal plane in which the planar structure is located, and may be referred to as a third direction. The driving arms 220 have at least two driving arms 220, and the at least two driving arms 220 are respectively arranged near two side edges of the planar structure arranged along the second direction; and preferably, the two driving arms 220 are symmetrically disposed about a central axis of the planar structure in the first direction. In some embodiments, the driving rail 210 may be provided as one, that is, the at least two driving arms 220 are connected to the one driving rail 210 and simultaneously driven by the orientation of the driving rail 210. In other embodiments, the driving tracks 210 are arranged in a manner matching the number or positions of the driving arms 220, for example, one driving track 210 is arranged on each side of the platform structure 110 along the second direction, and the two driving tracks 210 are used for driving a plurality of driving arms 220 arranged on each side.

In one embodiment, the drive arm 220 is slidably coupled to the drive rail 210, with the drive rail 210 being correspondingly configured as an I-shaped rail. A cross bar is further provided between the at least two driving arms 220, and the cross bar is arranged along the first direction and is connected to the two driving arms 220 at both ends, respectively. The above-mentioned manner of synchronous driving according to the "T-shaped belt driving stepper motor" is that the belt is connected to the cross bar, and the belt is driven by the driving stepper motor to drive the cross bar to move in the second direction, so that the scanning member 300 connected to the driving arm 220 can move in the second direction to realize scanning. To ensure the driving accuracy, a travel detecting assembly configured to be able to detect the driving accuracy of the stepping motor, i.e., the stepping accuracy, may also be provided. The apparatus may further include a control unit 400, where the control unit 400 has at least a capability of controlling the output parameters of the stepper motor to control the travel accuracy of the scanning member 300 based on the step accuracy data transmitted from the travel detection unit in combination with manual and/or program automatic regulation.

The control unit 400 also has at least the following functions: the control part 400 is electrically connected to the wind pressure auxiliary structure, especially the wind suction unit therein, so as to control at least the output parameters thereof, wherein the output parameters of the wind suction unit at least can comprise start and stop, output power and the like; the control part 400 is electrically connected to the scanning member 300 to acquire the scanning data transmitted thereto and bidirectionally control the operation parameters of the scanning member 300, which may include at least start-stop, definition selection, height of each light capturing unit 310 in the scanning member 300 in a third direction, data transmission format, and the like.

As shown in fig. 3, in the present embodiment, the scanning member 300 is generally configured as a bar-shaped configuration, which can be connected to symmetrically disposed driving arms 220 at two ends thereof in a manner of crossing over the platform structure 110 along the first direction, and can be moved relative to the platform structure 110 and the scanning object placed thereon along the first direction under the driving of the driving arms 220. At least one light capturing unit 310 is provided in the scanning member 300, and preferably, a plurality of light capturing units 310 are provided sequentially in an axial direction of the scanning member 300, wherein the axial direction is in the same direction as the first direction in the state of the scanning member 300 shown in the figure after being mounted.

The light capturing unit 310 is substantially similar to a photographing device such as a camera or a video camera, and functions to capture all or most of light within a predetermined viewing angle range thereof and convert the light into a digital image signal using a photosensitive element. In the present embodiment, the light capturing units 310 are set to Jiao Shuxing, the field of view ranges of which are fixed in size when no movement of the light capturing units itself relative to the subject is generated, and in order to obtain a high-precision image, that is, high-resolution image data, the field of view of each light capturing unit 310 should be set smaller as well, but this causes one light capturing unit 310 to capture a high-definition image of a part of the scan subject only during the relative movement with the scan subject. For the high-definition images of at least one part of the scanned object, which are acquired by the light capturing units 310 designed for use, a common way to acquire the complete image information of the scanned object is to combine the high-definition images of the parts acquired by the light capturing units 310 according to operations such as splicing, de-duplication, optimization and the like at corresponding positions, so that the complete high-definition scanned image of the scanned object can be finally obtained. Here, in order to obtain a complete view angle of the scanned object and a cost of the camera, it is a conventional solution to arrange the above-mentioned several light capturing units 310 at equal intervals, each light capturing unit 310 is responsible for capturing an image content of one of the fields of view, and when the scanning member 300 itself is not moving, the sum of fields of view of all the light capturing units 310 should at least include at least one physical range of the scanned object described by a side length. Preferably, when scanning starts, the initial position of the scanning member 300 should be set near one of the edges of the scanned object. This solution has a certain convenience and simplicity, since it can bring a certain advantage to the later image combination process by equally arranging several light capturing units 310 of the same parameters. Because the captured images are relatively fixed in size, depth of field and position, and the area and vertical length of overlapping parts of adjacent captured images are relatively fixed. When the later combination processing is carried out, the program can carry out the image combination operation according to the preset fixed duplication removal, deletion and collage parameters after only some simple verification and check works. In addition, as a matching, the optical path design of the scanning structure also has a certain relation with the light capturing units 310, and under the conventional arrangement, a plurality of linear light sources or uniform light sources and a plurality of light capturing units 310 are coaxially arranged in a one-to-one matching manner, that is, at least one light source with the irradiation direction coaxial with the light receiving direction of the light capturing units 310 exists near one light capturing unit 310. In this case, the light emitted from the plurality of light sources can uniformly illuminate the scanning object, and the brightness of each region of the scanning object is theoretically maintained substantially uniform or has the same variation pattern based on the light sources configured with the same parameters. This provides a certain convenience for the combination of the later scan images in terms of general understanding, because based on the scan images with the same brightness in theory, the combination procedure can use the original version image to combine without or without largely adjusting parameters such as brightness, saturation, etc. the method can reduce the benefits caused by scan errors caused by defects of the planes of some scan objects, such as shadows, misplacement, blurring, resolution reduction, etc. in the scan images caused by factors such as bulges, twists, bends, defects, etc. on the planes, and can make some later remedies by uniformly arranged lamplight. However, the desired effect of the conventional arrangement described above may not be achieved entirely in practice, and although the uniform spacing of the light capturing units 310 can obtain a stable field of view image from the arrangement aspect of the light capturing units 310, the light capturing units 310 arranged at opposite edges cannot entirely cover the scanned object within the field of view thereof, and at least a part of the area is replaced by a planar structure outside the edges of the scanned object. The closer to the middle light capturing unit 310, the more effective image duty ratio can be obtained from the area duty ratio of the scanned object image in the field of view, whereas the light capturing unit 310 near the edge can obtain only 50-60% or even lower effective image duty ratio, depending on the number of light capturing units 310 set and involved in the scanning operation and the arrangement interval. At the edge position, because the effective image is lower in duty ratio and tends to be located at the edge position of the field of view of the single light capturing unit 310, and because of the arrangement of the optical paths of the camera, the acquired imaging definition tends to be high in the middle area of the field of view, the resolution of the edge area of the field of view is relatively lower and the distortion is serious, if the images appear in the light capturing units 310 close to the middle, the edge images can be removed by preferentially combining the same image content parts with higher resolution and relatively lighter distortion in the effective images acquired by the light capturing units 310 adjacent to the images. However, it is difficult for the light capturing units 310 responsible for capturing the image of the edge of the scanning object to do so, firstly, it is difficult to preferentially combine the images acquired by the adjacent other light capturing units 310 for the effective images acquired by the light capturing units 310 of these parts, and in addition, from the perspective of the light sources arranged in cooperation with the light capturing units 310, the light sources located at the edge of the scanning object may be affected by the moving arms or other supporting parts and side wall parts set up at the edge to cause problems such as reflection, refraction and shadow different from those set up in the middle; in addition, even if the surrounding environment of the part of the light source is clear, the part of the platform structure 110 outside the edge of the scanned object is inevitably irradiated, and the problems of reflection, diffuse reflection and scattering caused by the part of the light source are relatively serious, so that the image data of the edge is more likely to generate sporadic defects, and the image is distorted.

In this embodiment, as shown in fig. 1, a new arrangement of the light capturing units 310 is proposed, and accordingly, in other preferred embodiments, the light sources matched with the light capturing units 310 have the same arrangement as the former. Specifically, in the present embodiment, if the distance between adjacent light capturing units 310 is referred to as a viewpoint distance L, the plurality of viewpoint distances L between the plurality of light capturing units 310 in the present embodiment are non-equally disposed; further, the device is arranged in a manner of sequentially shrinking from the center to the edge. The viewpoint distance L may be understood as a distance of a line connecting centers of lenses or photosensitive elements of the light capturing units 310, more precisely, a distance of a line thereof projected onto a plane parallel to a planar structure, which may be briefly understood as a lateral distance between adjacent light capturing units 310 when the planar structure is parallel to the ground.

As described above, the viewpoint distance L is sequentially reduced from the center to the edge, for example, assuming that the light capturing unit 310 closest to the center of the scanning member 300 is # 1, two adjacent light capturing units 310 respectively expanding toward the two edge directions thereof are # 2, and the viewpoint distances of # 1 and # 2 are L1; similarly, each 2# has another light capturing unit 3103# closer to the edge than 1# with the viewpoint distance L2 between 2# and 3 #; and so on, also have 4#, 5#, 6#, etc., with view distances L3, L4, etc., respectively. Then in this embodiment L1> L2> L3> L4> … > Ln. Assuming that the field of view of each light capturing unit 310 is uniform and has a generally conical configuration, the resulting object after clipping may be generally configured to have a rectangular field of view. As described above, the fields of view of two adjacent light capturing units 310 have overlapping, and the overlapping area is also substantially rectangular in shape in the case of the simplified rectangular field of view, and the width thereof along the arrangement direction of the light capturing units 310 may be referred to as the overlapping width D, and since the light capturing units 310 have no deflection or displacement in the viewing angle in the longitudinal direction, it can be understood that the length of the overlapping area is a fixed value, and the size of the overlapping width D determines the area of the overlapping area. As described above, the viewpoint distance is sequentially reduced from the middle to the edge, and accordingly, in the case where the fields of view are uniform, the overlap width D is sequentially increased from the middle to the edge, that is, the area of the region where the fields of view of the adjacent light capturing units 310 near the edge overlap is larger than that of the adjacent light capturing units 310 near the middle.

The above arrangement has the advantage that a large number of light capturing units 310, which were originally used to collect the middle region of the scanned object, are extrapolated towards the edges, so that the scanning quality of the edges is greatly improved without losing or losing a large amount of the middle scanning quality. In particular, as described above, since the light capturing unit 310 located near the middle area of the scanned object can be completely covered by the content of the scanned object, and the light path located in the middle is only responsible for illuminating the scanned object and is therefore rarely interfered by the external environment or the internal environment of the scanned object, the image resolution, the reality and the quality of the image acquired by the light capturing unit 310 of this part are higher, the procedure can be used to process the detail problem in the image by a simpler procedure, faster data processing and smaller system occupation when processing the image acquired by the light capturing unit 310 of this type, and for the above reasons, the image acquired by the middle part can still obtain relatively better image quality at the part of the edge of the field of view, such as distortion is relatively easier to process, and the image acquired by the light capturing unit 310 adjacent thereto can also obtain scanned images with relatively good quality because of the image near the middle part, so that the image can be combined by splicing the overlapping part, and the overlapping part can be used to perform image optimization more quickly and simply, relatively without too much overlapping part to borrow from each other. The present embodiment thus sets the viewpoint distance of the light capturing unit 310 of the middle portion to be relatively large while also being able to secure the quality of the middle scanning portion. In contrast, as described above, since the effective area portion in the field of view of the edge portion is too small and the light is easily affected by various wall and plane structures, the image of the edge portion needs more reference images with better quality to be corrected, combined and preferentially saved, in this embodiment, the view point distance L of the light capturing unit 310 near the edge region is reduced, and then the increase of the overlapping width D is brought, so that the scanned image at the edge portion has more opportunities to be mutually referred to and corrected with the image scanned adjacently, so that the image combination can exclude the interference of light, environment and the like, and a better image stitching effect is obtained. Especially for some scanning situations, the size of the scanning object is not fixed, the boundary of the scanning object just exceeds the field of view of the light capturing unit 310 capable of capturing the most edge position of the scanning object, at this time, to ensure that the whole range of the scanning object can be collected by the light capturing unit 310, another light capturing unit 310 closer to the edge is controlled to be started, under the condition of regular equidistant arrangement, only a small part of the field of view range of the light capturing unit 310 can obtain some effective images about the scanning object, because the images are located at the edge of the field of view of the light capturing unit 310, and the units are located in the edge environment with relatively more interference factors, and meanwhile, the overlapping part of the units and the adjacent light capturing unit 310 is less in the conventional arrangement, so that great difficulty is generated when the part of images are subjected to post-processing and combining, and then the part of images are most likely to generate undesirable problems such as distortion, loss and omission. For scanned objects, the content of the edges is often equally important as the content of the center, for example, some of the contents written on the edges of pages, page labels, signatures, etc. are very important for the integrity, validity, and readability of the content of the whole page. Therefore, by adopting the arrangement scheme of the light capturing units 310 provided in this embodiment, overlapping fields of view between adjacent light capturing units 310 responsible for scanning the edges of the scanned object are larger, and in addition, the overlapping portions are relatively closer to the center of the field of view of each light capturing unit 310, and based on two overlapping partial images with better quality, combination and stitching are performed, so that most of image distortion problems caused by edge interference factors can be relatively eliminated, and better effect can be obtained in the scanning of the edges.

Preferably, in this embodiment, each light capturing unit 310 is further provided with at least one driver 320. The driver 320 is drivingly connected to the light capturing unit 310 to provide movement drive thereof in a third direction. The driver 320 may be configured as a motor that enables lifting or lowering of the light capturing unit 310 by rotation and cooperation of gears.

In addition, according to the above, it is preferable that the light sources are also gradually widened from the middle to the edge from each other in a manner of matching the light capturing unit 310. The light sources positioned near the center of the scanning object are relatively arranged in a scattered manner, because the environment of the middle part is stable and single, the influence on light is small, and the adjacent light sources can provide certain additional light for the peripheral position, so that only a few light sources with larger intervals are needed to provide stable and uniform illumination for the middle part of the scanning object; however, for the scanned object at the edge part, if the scanned object is arranged in a normal equidistant mode, firstly, other structures such as a supporting arm, a supporting plate, a surrounding baffle and the like existing at the edge can cause refraction, reflection and scattering to the light path, so that the illumination is not ideal; second, even if the edge position is not affected by the above-described other structures, portions of the mesa structure 110 beyond the edge of the scan object are necessarily present, and inevitably, these portions affect the irradiation effect of the light source due to light absorption, reflection, refraction, scattering, and the like; again, unlike the light source in the middle, the light source at the edge lacks at least the auxiliary illumination brought by another adjacent light source, causing the natural defect of the illumination effect in the place, however, even if additional light source devices are arranged on the periphery on the basis of this, the cost or energy consumption is not increased differently from the addition. Compared with the central portion, in this embodiment, the light sources at the edge portion are more concentrated and the interval is shorter, so that one light source can obtain more auxiliary illumination from the adjacent light sources, the illumination at the edge portion cannot generate more than expected loss due to the additional components or the platform structure 110, the losses can be counteracted by the enhanced illumination, and meanwhile, the image acquisition of the light capturing unit 310 in the area is more facilitated, and the two auxiliary illumination can enable the image acquisition quality of the edge of the scanned object to be higher. In particular, the large-format scanning according to the present embodiment can scan, in addition to document files printed by handwriting or a printer, oil painting, ink painting, silk painting, and the like, and for such objects created using a drawing material different from a conventional writing or printing material, for example, a painting using an oily pigment, a mineral pigment, a carbon pigment, and the like, particularly, some ancient books, cultural relics, and antiques, the effect of light on the pigment color thereof is great. Light rays in special wave bands can affect pigments or components in the picture bottom to cause photo-aging, and finally cause problems of calligraphy and painting color fading, color change, picture bottom aging, weakness, fracture and the like, which are unacceptable especially for antiques with high value. Although the LED technology adopted at present can avoid emitting the light wave bands affecting the antique calligraphy and painting pigments to the greatest extent, firstly, the design requirement on the LED is very high, the conventional LED cannot be used, and secondly, the LED does not emit most of the infrared spectrum, but still generates heat, if the heat is concentrated in the middle position of the calligraphy and painting, there is still a great risk that the calligraphy and painting contents are thermally aged, and loss is caused. The scheme adopted in the embodiment can better avoid the problem, through the scheme of gradually concentrating the light source towards two edges, the region with denser light can be migrated from the center to the edge, and the common calligraphy and painting edge is a picture frame or has no white content, and the parts are free of content, so that the ageing and the deletion of the parts can be avoided, and more protective scanning can be performed on the basis of not changing the original structure of the calligraphy and painting.

Preferably, the driving arm may be configured to be capable of driving the scanning member up and down according to a third direction, for example, a structure shown in fig. 4, which is driven by a double screw driving manner that is relatively mature in the prior art, briefly, the rotating motor drives the double screw to rotate, and the moving table that is movably embedded on the double screw drives the driving arm itself or other structures in the driving wall that can be connected with the scanning member to move up and down on a sliding rail that is disposed along the third direction so as to drive the whole scanning member to move in the third direction. The driving scheme has a certain adaptability effect on the scanning object with a certain thickness, for example, the whole scanning component can be lifted upwards along a third direction aiming at the thicker scanning object so that the light capturing unit in the scanning component can be accurately focused, and the adjusting precision meets plus or minus 0.1mm. The double lead screws can realize high-precision driving, and have strong driving capability and good stability. In the state that the figure shows, the rotating electrical machines is not connected with screw drive, and during the in-service use, can connect through the mode that sets up the rotating head in the middle.

It should be noted that the above-described embodiments are exemplary, and that a person skilled in the art, in light of the present disclosure, may devise various solutions that fall within the scope of the present disclosure and fall within the scope of the present disclosure. It should be understood by those skilled in the art that the present description and drawings are illustrative and not limiting to the claims. The scope of the invention is defined by the claims and their equivalents. The description of the invention encompasses multiple inventive concepts, such as "preferably," "according to a preferred embodiment," or "optionally," all means that the corresponding paragraph discloses a separate concept, and that the applicant reserves the right to filed a divisional application according to each inventive concept.

Claims (9)

1. A non-contact scanning device at least comprises,

a machine (100) comprising at least a platform structure (110) for placing a scan object,

a scanning member (300) arranged transversely above the platform structure (110) in a second direction and adapted to acquire an image of a scanned object,

it is characterized in that the method comprises the steps of,

the scanning member (300) is configured to be movable over the platform structure (110) in a first direction to acquire an image of the scanning object, the scanning member (300) comprising a plurality of light capturing units (310) arranged linearly for acquiring at least a part of the image of the scanning object, wherein, in case that there is a viewpoint distance adjacent to the light capturing units (310), the light capturing units (310) are arranged in such a manner that the viewpoint distances taper sequentially from the center to the edge, the viewpoint distance being a pitch of the adjacent light capturing units (310), the viewpoint distance of the light capturing unit (310) near the center being configured to be larger than the viewpoint distance of the light capturing unit (310) near the edge.

2. The apparatus according to claim 1, wherein in the case of an arrangement in which the light capturing units (310) are tapered in accordance with a trend of the viewpoint distance from the center to the edge, the overlapping areas of the fields of view of adjacent light capturing units (310) are changed in a gradually increasing manner from the center to the edge, such that the image captured by the scanning means (300) with respect to the scanning object is relatively more in the area of the image at the edge position that can be corrected against each other.

3. The apparatus of claim 2, wherein the scanning member (300) further comprises a plurality of light sources arranged in the scanning member (300) in a tapered arrangement from the middle to the outside along with the light capturing units (310) in a manner capable of illuminating at least the field of view of each of the light capturing units (310).

4. A device according to claim 3, characterized in that the area of the scan object illuminated by at least two light sources at the same time at the edge position in the second direction is larger than the illuminated area at the intermediate position, so that the scan object edge is imaged by the light capturing unit (310) in a state of relatively good illumination.

5. The apparatus according to claim 4, wherein the scanning members (300) are connected to the machine (100) by driving arms (220) provided at both ends, respectively, to constitute a state of being suspended above the platform structure (110).

6. The apparatus according to claim 5, wherein each light capturing unit (310) is provided with at least one driver (320) configured to be able to adjust its own position in a third direction, the focal length of each light capturing unit (310) being able to be individually adjusted when the position is adjusted in the third direction.

7. The apparatus according to claim 6, wherein a driving structure (200) is provided in the machine (100), and comprises a driving rail (210) and driving arms (220), the driving rail (210) being provided on both sides of the machine (100) in a first direction, and one end of at least two driving arms (220) extending in a third direction being movably connected to the driving rail (210), such that a moving direction of the driving arms (220) is defined in the first direction of the driving rail (210).

8. The device of claim 7, wherein at least two drive arms (220) are connected by a cross bar, the drive structure (200) further comprising a drive assembly drivingly connected to the cross bar to move the drive arms (220) in the first direction.

9. The apparatus according to claim 8, characterized in that the platform structure (110) is provided with a partial pressure assist structure for assisting in flattening of the scanning object, which is configured to be able to flatten the scanning object on the platform structure (110) based on generating a negative pressure on the platform structure (110).