• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    Multi or hyperspectral camera to maintain the lateral magnification adjusting the focus that includes, in a box (4) at least 4 sensors (2), a lens (3) for each sensor (2), an external band pass filter (14) for each sensor (2), a calibration matrix, a battery (5) to provide energy, standardized tapes (7) for sending information to a microchip (8), a motor (16) for each sensor (2) so that the sensor (2), the lens (3) and the band-pass filter (14) move in unison to focus while maintaining the lateral magnification, where the multispectral camera is called the one that includes between 4 and 15 sensors (2) and hyperspectral camera which includes at least 16 sensors (2). These cameras with an external filter matrix are useful for registering multiple spectra emitted or reflected by an object or light source in a single optoelectronic device, with the option of manufacturing it as a universal structure thanks to using the dimensions and characteristics of a conventional camera. (Machine-translation by Google Translate, not legally binding)
    公开号:ES2819052A1
    申请号:ES202031019
    申请日:2020-10-07
    公开日:2021-04-14
    发明作者:Fernández-Balbuena Antonio Alvarez；Vilaboa Ricardo Bernárdez；Moliní Daniel Vázquez；Pinilla Santiago Mayorga；Manzanares Angela Gómez
    申请人:Universidad Complutense de Madrid；
    IPC主号:
    专利说明:

    [0002] Multi or hyperspectral camera to maintain lateral magnification by adjusting focus
    [0004] TECHNICAL SECTOR
    [0006] The present invention falls within the field of multiple image acquisition devices. More specifically, it refers to the field of multispectral and hyperspectral cameras.
    [0008] BACKGROUND OF THE INVENTION
    [0010] Multispectral and hyperspectral imaging were first developed to acquire remote images, in the fields of planetary research and astronomy. Subsequently, they have been given multiple applications in biology, medicine, chemistry, classification of objects in different industrial sectors and quality control. One of the areas where they are most used is agricultural engineering, through GIS ( geographical Information systems) systems, where the treatment of these data allows obtaining values of the crops such as humidity, possible diseases, etc. Another sector in which they have been found application is the study and conservation of cultural heritage because, as they are non-invasive images, they can be used on any object, however fragile it may be, obtaining data of great interest.
    [0012] Multispectral and hyperspectral cameras are currently used to obtain spectral images of different objects. Spectral images reproduce the object based on the wavelength that that object is reflecting, as these cameras emit at different wavelengths, sets of images of the object are obtained, each one of them due to a different wavelength. With these spectral images, a pixel by pixel spectral data cube can be generated to analyze the different behaviors of a sample against different wavelengths.
    [0014] The difference between a multispectral camera and a hyperspectral camera is not clearly defined and depends largely on the field of application and the number spectral images they can take. For some authors the limit is 15 images, for others 20.
    [0016] For the selection of a specific detection band in the multi or hyperspectral camera detector, the use of narrow profile band-pass filters is common. A correct selection of the filter matrix allows obtaining a spectral image according to the needs of the sample to be analyzed.
    [0018] Due to the interest of this type of cameras and the diversity of technical fields where they can be applied, a large number of devices have been developed.
    [0020] ES2524354T3 describes a digital camera system with at least two independent digital cameras, with a color filter element and a procedure to determine deviations in exposure times and / or amounts of light captured between, at least, two digital cameras independent of the digital camera system. It also contains a procedure for restoring a color balance for a digital camera system.
    [0022] Patent ES2344888T3 refers to a modular hyperspectral thermal imaging camera comprising an entry slot formed by a transparent perforation in a highly reflective environment, a telecentric imaging lens to create images telecentrically with the light on the slot and a detector for detecting the imaging light, further comprising a telecentric collimator having a negative aspherical lens and a positive aspherical and diffractive hybrid lens and is positioned between the slot and the detector, a transmissive diffraction grating between the collimator and detector, and a focusing lens between the transmissive diffraction grating and the detector to focus the imaging light onto the detector, the focusing lens being adapted to provide telecentric image rays, thereby forming a image on the detector.
    [0024] Patent US7149366B1 is a compact High Definition Hyperspectral Imaging System (HDHIS) for remote sensing in light aircraft for scanning hyperspectral imaging and high resolution photographic imaging. E1HDHIS comprises a sensor head having a hyperspectral scanner and a CCD digital camera. An airborne computer interacts with the sensor head to provide data acquisition, including hyperspectral fast display images and control functions. An alternative embodiment includes combining the HDHIS with a computerized multi-camera imaging system in the air (CAMIS) comprising four progressive scan cameras (CCD) connected to a set of interchangeable interference filters, to provide a spectrum imaging system. triple that can be operated by one person in a light aircraft.
    [0026] Patent application US201403200611 A1 describes a multi-camera multispectral display unit, including a display unit, a camera set and an image integration processing unit. In some embodiments, the camera array is configured such that at least one camera is located on each of the two or more sides of the display unit. In some embodiments, each camera comprises a color image sensor or a multispectral imager.
    [0028] Patent US2019273850A1 consists of methods, systems and apparatus for a hyperspectral pleoptic camera. A hyperspectral hyperoptic chamber can be configured with a filter in the aperture plane of the chamber. The filter can selectively transmit the radiated wavelengths to a microlength array, which can focus and transmit the wavelengths to an image sensor based, for example, on the location and intensity of the wavelengths. One or more lenses and / or an iris can be configured to collect, focus, and or transmit wavelengths to and from the filter. The filter can be located between two lenses, and the distance between the two lenses can be based on a diameter of an aperture in the pleoptic chamber.
    [0030] Patent US10574911B2 consists of a lens compound to connect to an interchangeable lens mount of a digital camera that has a single image sensor, the lens compound includes a body; a body-mounted single-mount connecting ring for connecting to the digital camera lens mount; at least two lenses of substantially identical focal length mounted on the body; and a different single or multiple band pass filter associated with each of the lenses, allowing the passage of at least one visible band and one non-visible band, selected from the group consisting of near infrared bands and ultraviolet light bands, through the filters to the sensor; wherein the lenses are of a substantially identical field of view and a substantially identical image circle in a image sensor sensor plane.
    [0032] In CN208223641U a hyperspectral imaging system is described, characterized in that the system includes: a hyperspectral imaging module, a control module and a motor; the hyperspectral imaging module includes: an objective lens and a detector, and the detector is coated in the image plane. Filters with different transmission wavelengths are arranged radially in the image plane from the center to the edge of the image plane; The control module and the detector are respectively connected to the motor, the control module is used to control the motor operation, so that the motor drives the detector to rotate and scan the target object with its center as the axis to obtain multiple bands different waves from the hyperspectral image of the target object.
    [0034] A technical problem that is not yet resolved in the state of the art is related to focusing, specifically to focusing on surfaces that are almost flat as could be the case with a painting. A classic painting can have a difference in relief of up to 5 cm, it is not observed with the naked eye, but measurements made in Picasso's Guernica revealed that there are areas with differences in distance of up to 3 cm. When we focus each of the detectors by the classical means using the objective focus, the lateral magnification ratio is defined by:
    [0036] s'
    [0038] where s ’is the image distance and s the object distance, therefore, when changing the object distance s, the lateral magnification changes and the image is larger, so the calibration is not correct. The present invention presents a system that maintains the lateral magnification of all the sensors so that the calibration is correct with small variations in the depth of the image.
    [0040] EXPLANATION OF THE INVENTION
    [0042] Multi or hyperspectral camera to maintain lateral magnification by adjusting focus.
    [0044] In this specification, by "multispectral camera" is understood the one that can detect between 4 and 15 spectral images and by hyperspectral camera the one that detects 16 or more spectral images.
    [0045] One aspect of the present invention refers to a multi or hyperspectral camera that includes, in a housing or box:
    [0046] - at least 4 sensors,
    [0047] - one lens for each sensor, forming a sensor-lens block,
    [0048] - an external band pass filter for each sensor,
    [0049] - a calibration matrix,
    [0050] - a battery to provide power,
    [0051] - standard tapes for sending information to a microchip,
    [0052] - a motor for each sensor so that the sensor, lens and filter move in unison to focus.
    [0054] In the case of a multispectral camera, it will include between 4 and 15 sensors and, in the case of a hyperspectral camera, it will include at least 16 sensors.
    [0056] The sensors can be chosen, preferably, between CMOS and CCD and, in a preferred embodiment, the filters can be removed or exchanged for other filters depending on the needs, they are removable and / or interchangeable filters.
    [0058] Each sensor, lens, and filter assembly records an image. These images have a predetermined size in the calibration that is done at a specific distance. If the image varies in size on the sensor, the calibration is no longer valid. Therefore, the present invention includes an integral motor that moves the sensor, lens and filter assembly to maintain focus. Figure 3 consists of a positive lens, where the object focal points (F) and the focal image (F ') of the same are observed, in addition the distance d corresponding to the displacement is indicated. Likewise, the representation of the object as and together with its image called y 'is observed in it. Figure 3 shows what happens if an object y moves a distance d: it happens that the image y 'moves a distance determined by the Gaussian equation and becomes y' d. When it becomes y ' d , the image increases in size, changing the lateral magnification, apart from being out of focus. The conventional approach consists of moving the lens with respect to the sensor, but this changes the relationship between object and image distance and changes the lateral magnification, thus focusing but there is a change in the size of the image. If we move the lens, filter and sensor by a distance equal to d (figure 3B), in the filter, lens and sensor assembly, the lateral magnification p 'is maintained so that the image is of equal size and is in focus. To this end, the invention includes a motor for each sensor-lens-filter assembly, so that the sensor and the lens move at the same time to focus; in this way it is possible to focus and leave the lateral magnification the same in all the sensor-lens-filter assemblies.
    [0060] In this specification, lateral magnification is understood as the quotient between the height (vertical size) of the image y ' and the height of the object y.
    [0062] These cameras with an external filter matrix are useful for registering multiple spectra emitted or reflected by an object or light source in a single optoelectronic device, with the option of manufacturing it as a universal structure thanks to using the dimensions and characteristics of a conventional camera.
    [0064] This type of multi and hyperspectral cameras has application in:
    [0065] - taking pictures
    [0066] - taking videos in real time
    [0067] - 3D reflectance measurement
    [0068] - estimation of relief and 3D deformation of the measured surface
    [0069] - the focus and the maintenance of the lateral magnification of each camera so that the images do not change in different focuses, being valid for focuses in a certain range -10cm approx., so it is very useful for frames that are not totally flat.
    [0071] They are of special relevance in technical fields where a high resolution capacity is required in objects with small geometric variations. For example, they can be very useful in areas such as the conservation of artistic heritage, art history and archeology. For example, it is possible to identify the use of different compositions of the materials within the same work of art, the use of different pigments or detect conservation interventions carried out in earlier times, among many other options.
    [0073] BRIEF DESCRIPTION OF THE DRAWINGS
    [0075] To complement the description that is being made and in order to help a better understanding of the characteristics of the invention, a set of drawings is attached as an integral part of said description where, for illustrative purposes and non-limiting, the following has been represented:
    [0077] Figure 1.- Hyperspectral camera (1) made up of 16 sensors (2) with lenses (3) attached to a rigid box (4). It has a battery (5). The chamber with external filter matrix (1) is screwed onto the thread (6) of the box (4). Motor (16) solidarity displacer with filter, lens and sensor. Schematic sectional view.
    [0079] Figure 2.- Hyperspectral camera (1). Schematic front view.
    [0081] Figure 3. Schematic ray tracing to explain focus keeping lateral magnification equal to calibration.
    [0083] Next, a list of the different elements represented in the figures that make up the invention is provided:
    [0084] 1 = hyperspectral camera
    [0085] 2 = sensor
    [0086] 3 = lens
    [0087] 4 = box
    [0088] 5 = battery
    [0089] 6 = thread
    [0090] 7 = ribbon
    [0091] 8 = microchip
    [0092] 9 = screws
    [0093] 10 = holes
    [0094] 11 = rear surface
    [0095] 12 = circular entrance pupil
    [0096] 13 = Cap with holes
    [0097] 14 = filters
    [0098] 15 = wiring
    [0099] 16 = motor
    [0101] PREFERRED EMBODIMENT OF THE INVENTION
    [0103] The present invention is illustrated by the following examples which are not intended to be limiting of its scope.
    [0104] Example 1.
    [0105] A camera was made with 16 Sony IMX219 CMOS sensors (2) of 3280x2464 pixels and 16 lenses (3) of focal length 3.6 mm, included in a compact box (4). Band pass filters (14) from 380 to 780 nm spaced 25 nm between them were included, starting with the FB380-10 and ending with the FB800-40, from Thorlabs, with FWHM spectral width between 10 and 40 nm. As shown in figure 1, the band pass filters are removable and interchangeable.
    [0107] The chamber was designed with 16 motors (16) (HANPOSE HPV4 with stepper motor 17HS3401S) of individual drive, these motors (16) have a linear travel of 10 cm. Each motor can jointly and individually move the filter (14), lens (3) and sensor (2) assembly with a precision of 1mm. This displacement is independent for each set so it allows the correct focus of each sensor (2) in the indicated displacement range. To determine the necessary displacement of the motor (16), the images obtained in each sensor-lens assembly are analyzed and an automated forward and backward movement is carried out with image capture, this micro-displacement allows, through image processing, to determine the correct direction displacement of the motor (1) for correct focus. This cycle is repetitive until the best focus is achieved, it is a contrast detection focus system that does not need additional elements to those provided in the system, understanding the hyperspectral camera as a whole system.
    [0109] Each filter + sensor + lens set has been manually focused previously at a certain distance that will be the operating distance of the system - the distance of displacement of the motors (16), they have also been individually calibrated to obtain the calibration matrix. This calibration matrix includes a factor k1 ( n, px, py) for the luminance of each pixel position and a factor k2 ( n, px, py) for the geometric deformations, where n is the number of the sensor (2) and px, py are the positions of each individual pixel.
    [0111] For the box (4), polyacid lactic acid (PLA) was used, a rigid biodegradable plastic material, in a dark color. The box (4) also included a battery (5), in a battery holder element, of 5V and 8000 mA to provide power to the system. I know used tapes (7) standardized to send information to a microchip (8) with a size of 100 mm wide x 100 mm high and 6 mm deep. In the front part of the box (figure 2) a lid (13) with holes was included; This front part was closed with the rear surface (11) by means of screws (9). These screws (9) have dimensions of 30 mm long and 10 mm wide and are passed through the holes (10) arranged in the rear surface (11) of the box (4).
    [0113] In this example, a model of circular entrance pupils (12) with a diameter of 10 mm was used, made in the lid (13) with holes that were manufactured with the same material as the box (4), easy to open by pressure. with clips for exchanging the filters (14) with a diameter of 9.8 mm and adjustable by means of a thread (6). In the lower corner of the box (4) an outlet for battery charging (5) was located, as well as the necessary control wiring (15).
    权利要求:
    Claims (3)
    [1]
    1. Multi or hyperspectral camera to maintain the lateral magnification adjusting the focus that includes, in a box (4):
    - at least 4 sensors (2),
    - one lens (3) for each sensor (2),
    - an external band pass filter (14) for each sensor (2),
    - a calibration matrix,
    - a battery (5) to provide energy,
    - tapes (7) standardized for sending information to a microchip (8), - a motor (16) for each sensor (2) so that the sensor (2), the lens (3) and the filter (14) pass band move in unison to focus while maintaining lateral magnification,
    where the multispectral camera is called the one that includes between 4 and 15 sensors (2) and the hyperspectral camera is the one that includes at least 16 sensors (2).
    [2]
    Camera according to claim 1, in which the sensors (2) are selected from CCD and / or CMOS.
    [3]
    Camera according to any of the preceding claims, in which the band pass filters (14) are interchangeable and / or removable.
    类似技术:
    公开号 | 公开日 | 专利标题
    CN100592029C|2010-02-24|Ranging apparatus
    CN104567668B|2017-10-24|Scanning means for space measurement
    ES2635094T3|2017-10-02|Procedures and apparatus for confocal imaging
    ES2478637T3|2014-07-22|Three-dimensional monocular imaging
    ES2617664T3|2017-06-19|Autofocus procedure and autofocus device
    CN101793829B|2012-07-11|Fluorescent microscopic imaging method and system thereof
    US9213228B2|2015-12-15|Device and method for measuring a camera
    US20050260741A1|2005-11-24|Wide field image for quantitative analysis of microarrays
    US20050206874A1|2005-09-22|Apparatus and method for determining the range of remote point light sources
    CA2665980A1|2006-10-26|Dual-modality imaging using a pet scanner and an optical detector
    US11092794B2|2021-08-17|Angularly-selective illumination
    ES2800680T3|2021-01-04|Line scan and sample scan multimodal confocal microscope
    CN105203507B|2020-06-12|Telecentric wide-field fluorescence scanning imaging system and method
    RU2540453C2|2015-02-10|Microscope, imaging device and imaging system
    JP6787902B2|2020-11-18|A method and goniometer for measuring at least one characteristic variable regarding the illumination or radiation of a light source in a direction-dependent manner.
    EP3015817B1|2019-12-18|Optical method of and apparatus for determining positions and orientations of a plurality of mirrors in the field of view of an objective lens
    ES2819052B2|2022-02-02|MULTI OR HYPERSPECTRAL CAMERA TO MAINTAIN LATERAL ENHANCEMENT BY ADJUSTING THE FOCUS
    US10948506B2|2021-03-16|Slide rack carousel
    CN206905901U|2018-01-19|A kind of auto-focusing hyperspectral imager
    US10107620B2|2018-10-23|Image pickup apparatus
    US11030776B2|2021-06-08|Calibration of a light-field imaging system
    CN112513594A|2021-03-16|Hyperspectral scanner
    RU2383846C2|2010-03-10|Multi-channel sighting-observing optoelectronic device
    CN105352923A|2016-02-24|Fast wide-field-of-view volume holographic fluorescent microscopic imaging system
    US20100279338A1|2010-11-04|Cell carrier coding
    同族专利:
    公开号 | 公开日
    ES2819052B2|2022-02-02|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    US3917390A|1972-09-15|1975-11-04|Spectral Data Corp|Effective focal length adjusting additional lens system for multispectral camera-projector|
    JPS63116339A|1986-11-05|1988-05-20|Minolta Camera Co Ltd|Convergence measuring method for color cathode-ray tube|
    US5383059A|1992-06-11|1995-01-17|Minolta Co., Ltd.|Nonvariable transverse magnification focussing method and lens systems|
    WO1994015184A1|1992-12-28|1994-07-07|Michele Hinnrichs|Image multispectral sensing|
    US5986758A|1998-08-18|1999-11-16|The United States Of America As Represented By The Secretary Of The Air Force|Diffractive optic image spectrometer |
    CN101271023A|2008-02-29|2008-09-24|深圳大学|Imaging structure and its use method for diffraction optical imaging optical spectrometer with constant lateral magnification|
    US20130242131A1|2010-09-28|2013-09-19|Leica Geosystems Ag|Digital multi-spectral camera system having at least two independent digital cameras|
    法律状态:
    2021-04-14| BA2A| Patent application published|Ref document number: 2819052 Country of ref document: ES Kind code of ref document: A1 Effective date: 20210414 |
    2022-02-02| FG2A| Definitive protection|Ref document number: 2819052 Country of ref document: ES Kind code of ref document: B2 Effective date: 20220202 |
    优先权:
    申请号 | 申请日 | 专利标题
    ES202031019A|ES2819052B2|2020-10-07|2020-10-07|MULTI OR HYPERSPECTRAL CAMERA TO MAINTAIN LATERAL ENHANCEMENT BY ADJUSTING THE FOCUS|ES202031019A| ES2819052B2|2020-10-07|2020-10-07|MULTI OR HYPERSPECTRAL CAMERA TO MAINTAIN LATERAL ENHANCEMENT BY ADJUSTING THE FOCUS|
    [返回顶部]