WO2006081535A2 - Rolling-reset imager with optical filter - Google Patents
Rolling-reset imager with optical filter Download PDFInfo
- Publication number
- WO2006081535A2 WO2006081535A2 PCT/US2006/003158 US2006003158W WO2006081535A2 WO 2006081535 A2 WO2006081535 A2 WO 2006081535A2 US 2006003158 W US2006003158 W US 2006003158W WO 2006081535 A2 WO2006081535 A2 WO 2006081535A2
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- light
- imaging system
- set forth
- illumination
- rolling
- Prior art date
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N23/00—Cameras or camera modules comprising electronic image sensors; Control thereof
- H04N23/70—Circuitry for compensating brightness variation in the scene
- H04N23/75—Circuitry for compensating brightness variation in the scene by influencing optical camera components
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N23/00—Cameras or camera modules comprising electronic image sensors; Control thereof
- H04N23/70—Circuitry for compensating brightness variation in the scene
- H04N23/73—Circuitry for compensating brightness variation in the scene by influencing the exposure time
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N23/00—Cameras or camera modules comprising electronic image sensors; Control thereof
- H04N23/70—Circuitry for compensating brightness variation in the scene
- H04N23/74—Circuitry for compensating brightness variation in the scene by influencing the scene brightness using illuminating means
Abstract
An imaging system (100,200) comprises a rolling-reset imager (110) that forms an electronic image of an object (160), a light source (130) illuminating the object (160) with pulsed light, and a bandpass optical filter (170) disposed between the object (160) and the rolling-reset imager (110). The pulsed light has an illumination frequency spectrum and an illumination pulse width defining an effective exposure time for forming the image of the object. The bandpass optical filter (170) has a frequency pass band permitting transmission of a significant portion of the illumination frequency spectrum while at least approximately inhibiting transmission of at least some light having frequencies outside the illumination frequency band.
Description
ROLLING-RESET IMAGER WITH OPTICAL FILTER
Related Application
[0001] This application claims priority to U.S. Patent Application No.
11/045,214, entitled "Rolling-Reset Imager With Optical Filter" filed January 27, 2005, which is incorporated by reference herein.
Technical Field
[0002] This application relates generally to optical systems and elements and more particularly to imaging systems, such as those useful for reading bar codes.
Background
[0003] Common imagers, such as interline transfer charge-coupled devices
(IT-CCDs) and certain complementary metal oxide semiconductor (CMOS) cameras, such as so-called 4-T pixel sensors (also known as frame-shuttered imagers), form an electronic image by simultaneously exposing all of its pixel elements to the object to be imaged. To image a moving object with such an imager, a frame shutter can be provided to briefly open and thereby to momentarily expose all of the imager's pixels at the same time, resulting in a "freeze frame" image. The time for which the shutter remains open - the frame exposure time - determines the maximum speed at which the object to be imaged can move while producing an adequate quality image. While mechanical shuttering can facilitate satisfactory imaging of fast moving objects, mechanical shuttering mechanisms adversely affect the complexity, cost, size, weight, power, reliability, and durability of an imaging system.
[0004] On the other hand, a rolling-reset imager, such as certain CMOS cameras, forms an image by sequentially activating individual rows of pixels within the pixel grid array, cycling through every row at a rate equal to the imager's frame rate. Each row is exposed for N units of time during each frame, where N specifies
the exposure time. This is accomplished by enabling gathering of pixel values for a row N rows before that particular row is to be read out. The readout process clears the row. This method enables the imager to capture images over a wide range of intensity, as each row can be exposed for as little as one unit time and for as long as the entire frame time. An unfortunate consequence of this exposure method is that each row is exposed at a slightly different time. If N = 1 , for example, then each row exposes sequentially. If a longer exposure time (N > 1) is implemented, then each row is staggered by 1/N of the total exposure time. If the imager is trying to capture a moving object, this staggered exposure causes motion artifacts. For example, if a thin vertically oriented object, such as a pencil, moves from left to right in front of such an imager at a sufficiently high speed, the image will be captured as a diagonally oriented pencil, due to the effects of staggered exposure time.
[0005] Rolling-reset CMOS imagers are generally less expensive than CCD imagers due to the relative ease of the CMOS process compared to the CCD process, and rolling-reset CMOS imagers are generally less expensive than frame- shuttered CMOS imagers since they typically have fewer transistors per pixel. However, it is challenging to operate a rolling-rest imager in a freeze-frame mode of operation. In order for all pixels to get exposed at the same time, each row must be set up to expose for the entire frame time. This large exposure time causes considerable motion blur effects. A mechanical shutter can be used in conjunction with a full frame exposure, to limit the intrusion of light to a narrow time period, corresponding to the desired exposure time. However, a mechanical shutter can be bulky, expensive, and less reliable than all-electronic means.
Summary
[0006] According to one embodiment, an imaging system comprises a rolling- reset imager that forms an image of an object, a light source illuminating the object, and an optical filter disposed between the object and the rolling-reset imager. The pulsed light from the light source has an illumination frequency spectrum and an illumination pulse width defining an effective exposure time for forming the image of the object. The optical filter has a frequency pass band permitting transmission of a
" ' " "" ~! -~x:~i frequency spectrum while at least approximately
inhibiting transmission of at least some light having frequencies outside the illumination frequency spectrum.
[0007] According to another embodiment, a method illuminates an object with illumination light in a given frequency range, so that the illumination light reflects from the object along with background ambient light. The method filters the reflected light so as to attenuate at least some of the background ambient light by a greater attenuation factor than the illumination light. The method forms a pixelized image based on the filtered light on a rolling-reset basis.
[0008] Additional details concerning the construction and operation of particular embodiments are set forth in the following sections with reference to the below-listed drawings.
Brief Description of the Drawings
[0009] Figure 1 is a diagram of an imaging system according to one embodiment.
[0010] Figure 2 is a diagram of a bar code reading system according to another embodiment.
[0011] Figure 3 is a flowchart of an imaging methods according to one embodiment.
[0012] Figure 4 is a flowchart of a bar code reading method according to one embodiment.
Detailed Description of Embodiments
[0013] With reference to the above-listed drawings, this section describes particular embodiments and their detailed construction and operation. As one skilled in the art will appreciate in light of this disclosure, certain embodiments are capable of achieving certain advantages over the known prior art, including some or all of the
following: (1 ) enabling the utilization of more economical rolling-reset imagers, such as CMOS rolling-reset imagers; (2) elimination of the need to use a physical shuttering mechanism; (3) suppression of background illumination; and (4) avoidance of visible flickering from the illumination source, which can be discemable and annoying to human observers. These and other advantages of various embodiments will be apparent upon reading the remainder of this section.
[0014] Figure 1 is a diagram of an imaging system 100 according to one embodiment. The imaging system 100 comprises a rolling-reset imager 110, which may be of the CMOS type. The rolling-reset imager 110 is mounted on a printed circuit board 120. The imaging system 100 also comprises one or more light sources 130, which can also be mounted on the printed circuit board 120, as shown. One purpose of the light sources 130 is to provide pulsed illumination to facilitate imaging and to freeze the object motion by defining the exposure time. Any arrangement of any number of light sources can accomplish that goal. The light sources 130 are preferably light emitting diodes (LEDs). The light sources 130 emit light of a wavelength within the sensitivity range of the imager 110, which may be visible light or near infrared (near-IR) light, for example. The use of pulsed LED illumination in the near-IR wavelength range from about 700 nm (nanometers) to about 950 nm may be particularly advantageous in some applications, as discussed below.
[0015] Placed in front of the imager 110 is a lens 140, which provides a field of view 150, in which is an object 160 to be imaged. In one use of the imaging system 100, the object 160 is an optical code, such as a bar code. Disposed between the lens 140 and the object 160 is an optical filter 170. An enclosure 180 covers the imager 110 and the lens 140 except where the optical filter 170 is located across the field of view 150, so that all light reaching the imager 110 passes through the optical filter 170, preferably after reflecting off the object 160.
[0016] The optical filter 170 ideally has a lowpass, highpass, or bandpass frequency response with a pass band matching as nearly as possible the spectrum of the light generated by the light sources 130. In this way, the object 160 can be
. . ... . = „ „ — ,___ 4U^ light sources 130 are illuminating the object 160
but not when the light sources 130 are not illuminating the object 160. Other light, such as background ambient light, having frequencies outside of the pass band of the optical filter 170, is desirably attenuated by the optical filter 170, preferably to an extent that such other light does not appreciably register at the imager 110. For example, if illumination sources 130 are near-IR LEDs emitting at a wavelength of 850 nm, and the background ambient illumination is fluorescent lighting, having little emission in the near-IR range, useful versions of the optical filter 170 include WRATTEN® #87 IR filter, available from Eastman Kodak Co., Rochester, New York; CR-39® IR longpass filter available from Opticast, Inc., Findlay, Ohio; as well as R- 72 IR pass filter, RG715 IR longpass filter, and RT830 bandpass filter, available from various sources such as Edmund Industrial Optics, Barrington, New Jersey, which passes wavelengths longer than 700 nm with high transmittance.
[0017] In use, the imaging system 100 can form freeze-frame images of the object 160 as it moves across the field of view 150. In this mode of operation, the light sources 130 are turned on for a fraction of the imager 110 frame time. The rows of the imager 110 are set to expose for an entire frame time, so that all rows are exposing during the time of the illumination pulse. For bar code reading, the exposure time per frame (and thus the pulse width of the illumination) should satisfy the following relation: TEXP = U/V, where U is the (minimum) unit width of a bar or space and V is the maximum velocity at which the bar code can move across the field of view 150.
[0018] The light sources 130 can be pulsed or strobed periodically with a pulse rate and duty cycle set to match a desired exposure time. The frame rate of the imager 110 and strobing frequency or pulse rate can be set, within the limits of the imager 110, to satisfy the following relation: FRMIN = V/(WF-Wo), where FRMiN is the minimum frame rate, V is the velocity at which the bar code moves across the field of view 150, WF is the width of the field of view 150 in the direction of the velocity, and Wo is the width of the object 160 in the direction of the velocity. Satisfying that relation ensures that the entire object 160 is seen by the imager 110 when it moves through the field of view 150. If the light from the light sources 130 is not visible, then the frame rate can be quite low without generating annoying visible
flicker. Visible light pulses at a frequency of about 50 Hertz (Hz) or less can cause a flicker effect that is distracting to the human eye. The use of near-IR illumination is advantageous for another reason as well - namely, that near-IR LEDs are capable of handling significant pulse overdrive currents at low duty cycles, enabling bright illumination for the imager 110. The relatively low frame rate needed to ensure capture of the object 160 allows the illumination LEDs to be pulsed at a very low duty cycle. For example, if the width of field WF is equal to 5 inches, the width of object Wo is equal to 1 inch, and the maximum object velocity is 50 inches per second, then the minimum frame rate FRMIN is 12.5 frames per second. If the object is a barcode with a minimum element width of 10 mils (0.010 inches), then the maximum exposure time (and therefore LED pulse width) is 200 μs (microseconds). The duty cycle of the LED would then be 200 μs x 12.5 Hz or 0.25%, which is quite small. An LED that is rated at 50 mA (milliamps) of continuous duty cycle current may be capable of 1 amp of current when pulsed at this low duty cycle. This increases the effective illumination on the target 160 by a factor of 20.
[0019] The optical filter 170 transmits with a relatively high transmittance the illumination generated by the light sources 130 and reflected off the object 160 while transmitting light of other frequencies with a relatively low transmittance. When the light sources 130 operate in the near-IR frequency range and the optical filter 170 has a near-IR pass band, the background ambient lighting is preferably provided by fluorescent lamps, which generate little near-IR energy. In that case, the imaging system 110 effectively discriminates illumination generated by the light sources 130 from background ambient light.
[0020] The imaging system 100 is useful in a wide variety of imaging applications. One example of an imaging application suitable for use of the imaging system 100 is reading optical codes, such as a bar code 260. One particular example of a bar code reader utilizing the principles of the imaging system 100 is the bar code imaging system 200 depicted in Figure 2. The bar code imaging system 200 utilizes a particular lens assembly 240 as well as a signal processor 290 to extract meaningful data from the image of the bar code 260. In particular, the imaging system 200 comprises a lens assembly 240 having rotationally symmetric
components comprising a front negative lens 242, followed by a spacer 244, followed by a rear positive lens 248. The spacer 244, which may be a washer or something similar, defines a central aperture 246, preferably circular in shape. The lens assembly 240 permits a more favorable trade-off between depth of field and light collection efficiency. Further details regarding the lens assembly 240 and its components are included in commonly assigned U.S. Patent Application No. 11/045,213, entitled "Imaging System with a Lens Having Increased Light Collection and a Deblurring Equalizer," filed January 27, 2005, which is incorporated by reference herein.
[0021] The lens assembly 240 preferably has a generalized axicon focus function, as it introduces a rather large amount of spherical aberration. The signal processor 290 is designed to cancel or compensate partially or fully for that aberration or blurriness caused by the lens assembly 240. The signal processor 290 preferably comprises a virtual scan line extraction module 292, a nonuniform pixel gain 294, and an equalizer 296. The virtual scan line extraction module 292, which is optional, reads and/or assembles samples or pixels from the imager 130 lying along one or more lines (i.e., "virtual scan lines") across the image at arbitrary angles or in another desired scan patterns. The nonuniform pixel gain 294, although also optional, can be advantageous in that it can suppress pixel nonuniformity that arises from such causes as differences in gain from pixel to pixel in the imager 110. The nonuniform pixel gain 294 is preferably an array of scale factors that are multiplied by the imager's intensity values on a pixel-by-pixel basis. The equalizer 296 is a filter, such as a digital finite impulse response (FIR) filter, whose transfer function preferably approximates the inverse of the modulation transfer function (MTF) of the lens assembly 240, so as to cancel or compensate for the blurriness or aberration caused by the lens assembly 240. Further details about the signal processor 290 are included in the above-referenced U.S. Patent Application No. 11/045,213.
[0022] Figure 3 is a flowchart of an imaging method 300 according to one embodiment. The method 300 illuminates (310) the object to be imaged, preferably with non-visible light, most preferably near-IR light. The illumination light, along with background light, reflect off the object. The method 300 filters (320) the reflected
light so as to transmit a significant amount of the reflected illumination light while attenuating to a greater degree other light, such as the ambient background light. On the basis of the light passing through the filter, the method 300 forms (340) an image of the object on a rolling-reset basis.
[0023] Figure 4 is a flowchart of an bar code reading method 400 according to one embodiment. The method 400 performs some of the same steps as the method 300, as indicated by use of the same reference numbers as used in Figure 3. Moreover, the method 400 focuses (430) the object to be imaged, preferably by means of optical elements, such as the lens 140 or the lens assembly 240, which provides a "soft focus" with extended depth of field and increased light collection efficiency. The filtering step 320 and the focusing step 430 may be performed in the opposite order from what is depicted in Figure 4. For example, the filter 170 in Figures 1 or 2 may be placed before or after the lens 140 or the lens assembly 240, respectively. The method 400 may also generate (450) a virtual scan line across the image, scale (460) the virtual scan line signal to compensate for nonuniformity in the background brightness level, and equalize (470) the resulting signal to compensate for aberration introduced by the focusing optics. Finally, the method 400 decodes (480) the bar code on the basis of the image formed at step 340 and any subsequent signal processing of the image data.
[0024] The methods and systems illustrated and described herein can exist in a variety of forms both active and inactive. For example, the signal processor 290 and the methods 300 and 400 can exist as one or more software programs comprised of program instructions in source code, object code, executable code or other formats. Any of the above formats can be embodied on a computer-readable medium, which include storage devices and signals, in compressed or uncompressed form. Exemplary computer-readable storage devices include conventional computer system RAM (random access memory), ROM (read only memory), EPROM (erasable, programmable ROM), EEPROM (electrically erasable, programmable ROM), flash memory and magnetic or optical disks or tapes. Exemplary computer-readable signals, whether modulated using a carrier or not, are signals that a computer system hosting or running a computer program can be
configured to access, including signals downloaded through the Internet or other networks. Concrete examples of the foregoing include distribution of software on a CD ROM or via Internet download. In a sense, the Internet itself, as an abstract entity, is a computer-readable medium. The same is true of computer networks in general.
[0025] The terms and descriptions used above are set forth by way of illustration only and are not meant as limitations. Those skilled in the art will recognize that many variations can be made to the details of the above-described embodiments without departing from the underlying principles of the invention. The scope of the invention should therefore be determined only by the following claims - and their equivalents - in which all terms are to be understood in their broadest reasonable sense unless otherwise indicated.
Claims
1. An imaging system (100,200) comprising: a rolling-reset imager (110) that forms an image of an object (160); a light source (130) illuminating the object (160) with pulsed light having an illumination frequency spectrum and an illumination pulse width defining an effective exposure time for forming the image of the object (160); and an optical filter (170) disposed between the object (160) and the rolling-reset imager (110), the optical filter (170) having a frequency pass band permitting transmission of a significant portion of the illumination frequency spectrum while at least approximately inhibiting transmission of at least some light having frequencies outside the illumination frequency spectrum.
2. An imaging system (100,200) as set forth in claim 1 , wherein the rolling-reset imager (110) is a CMOS rolling-reset imager.
3. An imaging system (100,200) as set forth in claim 1 , wherein the light source (130) comprises an LED.
4. An imaging system (100,200) as set forth in claim 1 , wherein the light source (130) is pulsed periodically at a pulse rate equal to a frame rate at which the rolling- reset imager (110) operates.
5. An imaging system (100,200) as set forth in claim 4, wherein the frame rate is about 50 frames per second or less.
6. An imaging system (100,200) as set forth in claim 1 , wherein the light source is pulsed periodically with a duty cycle that is approximately 0.25%.
7. An imaging system (100,200) as set forth in claim 1 , wherein the illumination frequency spectrum contains predominantly non-visible frequencies.
8. An imaging system (100,200) as set forth in claim 7, wherein the illumination frequency spectrum contains predominantly near-infrared frequencies.
9. An imaging system (100,200) as set forth in claim 8, wherein the illumination frequency spectrum contains major components within a wavelength range from about 700 nm to about 950 nm.
10. An imaging system (100,200) as set forth in claim 1 , wherein the optical filter (170) comprises a WRATTEN® #87 material.
11. An imaging system (100,200) according to claim 1 , wherein said light having frequencies outside the illumination frequency spectrum comprises background ambient light.
12. An imaging system (100,200) according to claim 11 , wherein the background ambient light is generated from one or more fluorescent light sources.
13. An imaging system (100,200) according to claim 1 , wherein the object (160) is a optical code.
14. An imaging system (100,200) according to claim 13, wherein the optical code is a bar code (260).
15. An imaging system (100,200) as set forth in claim 1 , wherein the object (160) experiences motion across at least a portion of a field of view while the rolling-reset imager (110) forms the image, and wherein the effective exposure time is sufficiently small so that the motion of the object (160) does not cause appreciable blurring of the image.
16. An imaging system (100,200) as set forth in claim 1 , further comprising: a rotationally symmetric lens assembly (240) disposed between the imager (110) and the object (160), the lens assembly (240) comprising a front negative lens (242), a rear positive lens (248), and an aperture (244) positioned between the front and rear lenses, the lens assembly (240) providing an extended depth of field for a given lens aperture size, whereby the lens assembly causes aberration compared to a well-focused lens; and an equalizer (296) connected to the imager (110), wherein the equalizer (296) at least partially compensates image data for the aberration caused by the rotationally symmetric lens assembly (240).
17. A method (300,400) comprising: illuminating (310) an object (160) with illumination light in a given frequency range, so that the illumination light reflects from the object (160) along with background ambient light; filtering (320) the reflected light so as to attenuate at least some of the background ambient light by a greater attenuation factor than the illumination light; and forming (340) a pixelized electronic representation of the image based on the filtered light on a rolling-reset basis.
18. A method (300,400) as set forth in claim 17, wherein the given frequency range is predominantly near-infrared.
19. A method (300,400) as set forth in claim 17, wherein the illuminating step comprises: periodically strobing the illumination light at a strobing frequency equal to a frame rate at which the rolling-reset image is formed.
20. A method (300,400) as set forth in claim 17, further comprising: passing (430) the filtered light through a lens assembly (140,240), thereby causing the object to be imaged with increased aberration; and equalizing (470) the data representing the image so as to at least partially compensate for the aberration introduced by the lens assembly (140,240).
21. A method (300,400) as set forth in claim 20, wherein the passing step comprises: passing the reflected light through a positive lens (242); blocking the light from a periphery region of the positive lens (242) while not blocking the light from a central aperture region of the positive lens (242); and passing the light from the central aperture region of the positive lens (242) through a negative lens (248).
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP06719838A EP1847116A4 (en) | 2005-01-27 | 2006-01-27 | Rolling-reset imager with optical filter |
CN200680005790.6A CN101151890B (en) | 2005-01-27 | 2006-01-27 | Rolling-reset imager with optical filter |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US11/045,214 US7499090B2 (en) | 2005-01-27 | 2005-01-27 | Rolling-reset imager with optical filter |
US11/045,214 | 2005-01-27 |
Publications (2)
Publication Number | Publication Date |
---|---|
WO2006081535A2 true WO2006081535A2 (en) | 2006-08-03 |
WO2006081535A3 WO2006081535A3 (en) | 2007-12-21 |
Family
ID=36696362
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/US2006/003158 WO2006081535A2 (en) | 2005-01-27 | 2006-01-27 | Rolling-reset imager with optical filter |
Country Status (4)
Country | Link |
---|---|
US (2) | US7499090B2 (en) |
EP (1) | EP1847116A4 (en) |
CN (1) | CN101151890B (en) |
WO (1) | WO2006081535A2 (en) |
Families Citing this family (21)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7823789B2 (en) | 2004-12-21 | 2010-11-02 | Cognex Technology And Investment Corporation | Low profile illumination for direct part mark readers |
EP1828958B1 (en) * | 2004-12-01 | 2012-05-16 | Datalogic ADC, Inc. | Triggering illumination for a data reader |
US7215493B2 (en) * | 2005-01-27 | 2007-05-08 | Psc Scanning, Inc. | Imaging system with a lens having increased light collection efficiency and a deblurring equalizer |
US7224540B2 (en) * | 2005-01-31 | 2007-05-29 | Datalogic Scanning, Inc. | Extended depth of field imaging system using chromatic aberration |
US8260008B2 (en) | 2005-11-11 | 2012-09-04 | Eyelock, Inc. | Methods for performing biometric recognition of a human eye and corroboration of same |
US8242476B2 (en) * | 2005-12-19 | 2012-08-14 | Leddartech Inc. | LED object detection system and method combining complete reflection traces from individual narrow field-of-view channels |
US20080142598A1 (en) * | 2006-12-14 | 2008-06-19 | Sik Piu Kwan | Method, system, and apparatus for an electronic freeze frame shutter for a high pass-by image scanner |
US8091788B2 (en) * | 2007-01-11 | 2012-01-10 | Datalogic Scanning, Inc. | Methods and systems for optical code reading using virtual scan lines |
US8222996B2 (en) | 2007-12-31 | 2012-07-17 | Intel Corporation | Radio frequency identification tags adapted for localization and state indication |
US8353457B2 (en) * | 2008-02-12 | 2013-01-15 | Datalogic ADC, Inc. | Systems and methods for forming a composite image of multiple portions of an object from multiple perspectives |
EP2248069B1 (en) | 2008-02-12 | 2013-08-28 | Datalogic ADC, Inc. | Systems and methods for forming a composite image of multiple portions of an object from multiple perspectives |
US8608076B2 (en) * | 2008-02-12 | 2013-12-17 | Datalogic ADC, Inc. | Monolithic mirror structure for use in a multi-perspective optical code reader |
JP5040776B2 (en) * | 2008-03-31 | 2012-10-03 | アイシン精機株式会社 | Imaging device |
WO2009158662A2 (en) * | 2008-06-26 | 2009-12-30 | Global Rainmakers, Inc. | Method of reducing visibility of illimination while acquiring high quality imagery |
US9418270B2 (en) | 2011-01-31 | 2016-08-16 | Hand Held Products, Inc. | Terminal with flicker-corrected aimer and alternating illumination |
US8408464B2 (en) | 2011-02-03 | 2013-04-02 | Metrologic Instruments, Inc. | Auto-exposure method using continuous video frames under controlled illumination |
US8836672B2 (en) | 2011-02-09 | 2014-09-16 | Dornerworks, Ltd. | System and method for improving machine vision in the presence of ambient light |
US9124798B2 (en) | 2011-05-17 | 2015-09-01 | Eyelock Inc. | Systems and methods for illuminating an iris with visible light for biometric acquisition |
US8830302B2 (en) * | 2011-08-24 | 2014-09-09 | Lg Electronics Inc. | Gesture-based user interface method and apparatus |
JP6396638B2 (en) * | 2013-03-29 | 2018-09-26 | マクセル株式会社 | Phase filter, imaging optical system, and imaging system |
US10909341B2 (en) * | 2016-10-26 | 2021-02-02 | Datalogic Automation, Inc. | Data processing reduction in barcode reading systems with overlapping frames |
Family Cites Families (89)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3614310A (en) | 1970-03-02 | 1971-10-19 | Zenith Radio Corp | Electrooptical apparatus employing a hollow beam for translating an image of an object |
US4082431A (en) | 1975-04-22 | 1978-04-04 | Minnesota Mining And Manufacturing Company | Image processing system using incoherent radiation and spatial filter hologram |
US4275454A (en) | 1978-12-01 | 1981-06-23 | Environmental Research Institute Of Michigan | Optical system phase error compensator |
US4308521A (en) | 1979-02-12 | 1981-12-29 | The United States Of America As Represented By The Secretary Of The Air Force | Multiple-invariant space-variant optical processing |
JPS5650469A (en) | 1979-10-02 | 1981-05-07 | Fuji Photo Film Co Ltd | Picture information reader |
US4804249A (en) | 1986-12-24 | 1989-02-14 | Honeywell Inc. | Optical filter for incoherent imaging systems |
US4864249A (en) | 1988-02-29 | 1989-09-05 | Reiffin Martin G | Nonslewing amplifier |
US5010412A (en) * | 1988-12-27 | 1991-04-23 | The Boeing Company | High frequency, low power light source for video camera |
US5354997A (en) | 1989-11-03 | 1994-10-11 | Battelle Memorial Institute | Method for increased sensitivity of radiation detection and measurement |
US5003166A (en) | 1989-11-07 | 1991-03-26 | Massachusetts Institute Of Technology | Multidimensional range mapping with pattern projection and cross correlation |
US5080456A (en) | 1990-02-26 | 1992-01-14 | Symbol Technologies, Inc. | Laser scanners with extended working range |
US5142413A (en) | 1991-01-28 | 1992-08-25 | Kelly Shawn L | Optical phase-only spatial filter |
US5278397A (en) | 1991-07-25 | 1994-01-11 | Symbol Technologies, Inc. | Multi-resolution bar code reader |
US5164584A (en) | 1991-06-24 | 1992-11-17 | Ncr Corporation | Optical scanner with power efficient lens |
GB2257280A (en) * | 1991-06-26 | 1993-01-06 | Asahi Optical Co Ltd | Non-scanning bar code reading apparatus |
US5332892A (en) | 1991-07-25 | 1994-07-26 | Symbol Technologies, Inc. | Optical systems for bar code scanners |
US5438187A (en) | 1991-11-01 | 1995-08-01 | Spectra-Physics Scanning Systems, Inc. | Multiple focus optical system for data reading applications |
JP2857273B2 (en) * | 1991-12-24 | 1999-02-17 | 科学技術振興事業団 | Aberration correction method and aberration correction device |
US5756981A (en) | 1992-02-27 | 1998-05-26 | Symbol Technologies, Inc. | Optical scanner for reading and decoding one- and-two-dimensional symbologies at variable depths of field including memory efficient high speed image processing means and high accuracy image analysis means |
US6347163B2 (en) * | 1994-10-26 | 2002-02-12 | Symbol Technologies, Inc. | System for reading two-dimensional images using ambient and/or projected light |
US5354977A (en) * | 1992-02-27 | 1994-10-11 | Alex Roustaei | Optical scanning head |
US5307175A (en) | 1992-03-27 | 1994-04-26 | Xerox Corporation | Optical image defocus correction |
US20030043463A1 (en) | 1992-03-30 | 2003-03-06 | Yajun Li | Athermalized plastic lens |
US6164540A (en) | 1996-05-22 | 2000-12-26 | Symbol Technologies, Inc. | Optical scanners |
US5331143A (en) | 1992-08-28 | 1994-07-19 | Symbol Technologies, Inc. | Optical scanner using an axicon and an aperture to aspherically form the scanning beam |
US5714750A (en) | 1992-12-04 | 1998-02-03 | Psc Inc. | Bar code scanning and reading apparatus and diffractive light collection device suitable for use therein. |
US5422472A (en) | 1992-12-04 | 1995-06-06 | Psc, Inc. | Optical symbol (bar code) reading systems having an electro-optic receptor with embedded grating rings |
US5479011A (en) | 1992-12-18 | 1995-12-26 | Spectra-Physics Scanning Systems, Inc. | Variable focus optical system for data reading |
US5347121A (en) | 1992-12-18 | 1994-09-13 | Spectra-Physics Scanning Systems, Inc. | Variable focus optical system for data reading |
US5371361A (en) | 1993-02-01 | 1994-12-06 | Spectra-Physics Scanning Systems, Inc. | Optical processing system |
US5315095A (en) | 1993-02-18 | 1994-05-24 | Symbol Technologies, Inc. | Beam with extended confinement for scanning purposes |
US5418356A (en) | 1993-02-18 | 1995-05-23 | Asahi Kogaku Kogyo Kabushiki Kaisha | Reading optical system |
JPH06266876A (en) * | 1993-03-15 | 1994-09-22 | Tokyo Electric Co Ltd | Two-dimensional code scanner |
EP0627643B1 (en) | 1993-06-03 | 1999-05-06 | Hamamatsu Photonics K.K. | Laser scanning optical system using axicon |
US5386105A (en) | 1993-06-07 | 1995-01-31 | Psc Inc. | Diffractive optical beam shaping methods and apparatus for providing enhanced depth of working range of bar code scanners |
US5446271A (en) | 1993-08-06 | 1995-08-29 | Spectra-Physics Scanning Systems, Inc. | Omnidirectional scanning method and apparatus |
US5623137A (en) | 1993-08-20 | 1997-04-22 | Welch Allyn, Inc. | Illumination apparatus for optical readers |
US5475208A (en) | 1994-01-27 | 1995-12-12 | Symbol Technologies, Inc. | Barcode scanner having a dead zone reducing system and a multifocal length collector |
US5521366A (en) * | 1994-07-26 | 1996-05-28 | Metanetics Corporation | Dataform readers having controlled and overlapped exposure integration periods |
US6073846A (en) | 1994-08-17 | 2000-06-13 | Metrologic Instruments, Inc. | Holographic laser scanning system and process and apparatus and method |
US5625495A (en) | 1994-12-07 | 1997-04-29 | U.S. Precision Lens Inc. | Telecentric lens systems for forming an image of an object composed of pixels |
US5770847A (en) | 1994-12-23 | 1998-06-23 | Spectra-Physics Scanning Systems, Inc. | Bar code reader with multi-focus lens |
US5814803A (en) | 1994-12-23 | 1998-09-29 | Spectra-Physics Scanning Systems, Inc. | Image reader with multi-focus lens |
KR19980702008A (en) | 1995-02-03 | 1998-07-15 | 마이클 지. 가브리지 | Method and apparatus for increasing field depth of optical system |
US5578813A (en) | 1995-03-02 | 1996-11-26 | Allen; Ross R. | Freehand image scanning device which compensates for non-linear movement |
US5646391A (en) | 1995-05-11 | 1997-07-08 | Psc, Inc. | Optical assembly for controlling beam size in bar code scanners |
US5745176A (en) * | 1995-10-12 | 1998-04-28 | Ppt Vision, Inc. | Machine-vision illumination system and method for delineating a lighted volume from an unlighted volume |
US5796528A (en) | 1996-02-15 | 1998-08-18 | Olympus Optical Co., Ltd. | Wide-angle lens system |
JPH1093856A (en) * | 1996-08-07 | 1998-04-10 | Hewlett Packard Co <Hp> | Solid-state image pickup device |
JP3725276B2 (en) * | 1997-01-23 | 2005-12-07 | フジノン株式会社 | Imaging lens |
CA2232997C (en) * | 1997-03-26 | 2001-07-10 | Dalhousie University | Dynamic target addressing system |
US6056198A (en) | 1997-08-07 | 2000-05-02 | Psc Scanning, Inc. | Optical scanning system and method including a collection system for range enhancement |
US6073856A (en) * | 1997-09-05 | 2000-06-13 | Dai Nippon Printing Co., Ltd. | Noncontact IC device |
GB2331481B (en) * | 1997-11-22 | 2002-09-04 | George Hayday | Clamping device |
KR100292236B1 (en) | 1998-03-24 | 2001-06-01 | 김명동 | Automatic cut-off and resupplying relay for transmission line |
US6069738A (en) | 1998-05-27 | 2000-05-30 | University Technology Corporation | Apparatus and methods for extending depth of field in image projection systems |
US6097856A (en) | 1998-07-10 | 2000-08-01 | Welch Allyn, Inc. | Apparatus and method for reducing imaging errors in imaging systems having an extended depth of field |
US6184534B1 (en) * | 1998-08-04 | 2001-02-06 | Eastman Kodak Company | Method of pulsing light emitting diodes for reading fluorescent indicia, data reader, and system |
US6152371A (en) | 1998-08-12 | 2000-11-28 | Welch Allyn, Inc. | Method and apparatus for decoding bar code symbols |
US6098887A (en) | 1998-09-11 | 2000-08-08 | Robotic Vision Systems, Inc. | Optical focusing device and method |
US6066857A (en) | 1998-09-11 | 2000-05-23 | Robotic Vision Systems, Inc. | Variable focus optical system |
JP2000089107A (en) * | 1998-09-17 | 2000-03-31 | Fuji Photo Optical Co Ltd | Image reading lens |
JP3072988B1 (en) * | 1999-02-22 | 2000-08-07 | オリンパス光学工業株式会社 | Imaging device |
US6633433B2 (en) | 1999-06-11 | 2003-10-14 | Symbol Technologies, Inc. | Beam shaping for optical scanners |
US6540145B2 (en) | 1999-06-11 | 2003-04-01 | Symbol Technologies, Inc. | Aperture controlled laser beam shaping techniques for scanning optical code |
US6250550B1 (en) | 1999-06-14 | 2001-06-26 | International Business Machines Corporation | Automated media storage library with variable focal length lens |
US6290135B1 (en) | 1999-07-23 | 2001-09-18 | Psc Scanning, Inc. | Multiple source/dense pattern optical scanner |
JP4083355B2 (en) * | 1999-10-08 | 2008-04-30 | オリンパス株式会社 | Imaging device |
JP4083356B2 (en) | 1999-10-08 | 2008-04-30 | オリンパス株式会社 | Imaging apparatus and imaging apparatus system |
JP4497671B2 (en) | 1999-10-19 | 2010-07-07 | キヤノン株式会社 | Image processing method of image reading apparatus |
WO2001045098A1 (en) | 1999-12-15 | 2001-06-21 | Koninklijke Philips Electronics N.V. | Optical scanning device |
FR2803067A1 (en) | 1999-12-23 | 2001-06-29 | Intermec Scanner Technology Ct | OPTOELECTRONIC DEVICE AND METHOD FOR ACQUIRING CODES USING AN OPTIMIZED TWO-DIMENSIONAL USEFUL SENSOR |
US6616046B1 (en) | 2000-05-10 | 2003-09-09 | Symbol Technologies, Inc. | Techniques for miniaturizing bar code scanners including spiral springs and speckle noise reduction |
US6689998B1 (en) | 2000-07-05 | 2004-02-10 | Psc Scanning, Inc. | Apparatus for optical distancing autofocus and imaging and method of using the same |
US6276606B1 (en) | 2000-08-18 | 2001-08-21 | Kenneth Liou | Full range bar code scanner |
US6536898B1 (en) | 2000-09-15 | 2003-03-25 | The Regents Of The University Of Colorado | Extended depth of field optics for human vision |
US7128266B2 (en) | 2003-11-13 | 2006-10-31 | Metrologic Instruments. Inc. | Hand-supportable digital imaging-based bar code symbol reader supporting narrow-area and wide-area modes of illumination and image capture |
US6420704B1 (en) * | 2000-12-07 | 2002-07-16 | Trw Inc. | Method and system for improving camera infrared sensitivity using digital zoom |
JP2002218295A (en) | 2001-01-18 | 2002-08-02 | Olympus Optical Co Ltd | Image pickup device |
US6891570B2 (en) * | 2001-01-31 | 2005-05-10 | Itt Manufacturing Enterprises Inc. | Method and adaptively deriving exposure time and frame rate from image motion |
US6832728B2 (en) * | 2001-03-26 | 2004-12-21 | Pips Technology, Inc. | Remote indicia reading system |
US7616238B2 (en) * | 2001-03-29 | 2009-11-10 | Given Imaging Ltd. | Method for timing control of an image sensor |
US6651886B2 (en) | 2001-04-13 | 2003-11-25 | Symbol Technologies, Inc. | Optical code readers with holographic optical elements |
EP1386041A1 (en) * | 2001-05-10 | 2004-02-04 | Knut Overaas | Erection system for the structure of a house |
TW589862B (en) * | 2001-12-11 | 2004-06-01 | Pixart Imaging Inc | Image capturing device and method |
US20050122422A1 (en) * | 2003-12-08 | 2005-06-09 | Kent Edward M. | Video camera synchronized infrared strobe inspection system |
US7643084B2 (en) * | 2003-12-22 | 2010-01-05 | Hoya Corporation | Lighting control apparatus |
US7234641B2 (en) | 2004-12-01 | 2007-06-26 | Datalogic Scanning, Inc. | Illumination pulsing method for a data reader |
US7204418B2 (en) * | 2004-12-08 | 2007-04-17 | Symbol Technologies, Inc. | Pulsed illumination in imaging reader |
-
2005
- 2005-01-27 US US11/045,214 patent/US7499090B2/en active Active
-
2006
- 2006-01-27 CN CN200680005790.6A patent/CN101151890B/en active Active
- 2006-01-27 WO PCT/US2006/003158 patent/WO2006081535A2/en active Application Filing
- 2006-01-27 EP EP06719838A patent/EP1847116A4/en not_active Withdrawn
-
2009
- 2009-02-26 US US12/393,838 patent/US8134621B2/en active Active
Non-Patent Citations (1)
Title |
---|
See references of EP1847116A4 * |
Also Published As
Publication number | Publication date |
---|---|
WO2006081535A3 (en) | 2007-12-21 |
US7499090B2 (en) | 2009-03-03 |
US20090153718A1 (en) | 2009-06-18 |
CN101151890A (en) | 2008-03-26 |
US20060164541A1 (en) | 2006-07-27 |
EP1847116A4 (en) | 2010-12-01 |
CN101151890B (en) | 2011-06-15 |
EP1847116A2 (en) | 2007-10-24 |
US8134621B2 (en) | 2012-03-13 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US7499090B2 (en) | Rolling-reset imager with optical filter | |
CN109416475B (en) | Beam splitting extended dynamic range image capture system | |
US7884868B2 (en) | Image capturing element, image capturing apparatus, image capturing method, image capturing system, and image processing apparatus | |
US8724921B2 (en) | Method of capturing high dynamic range images with objects in the scene | |
US8091788B2 (en) | Methods and systems for optical code reading using virtual scan lines | |
US20070242141A1 (en) | Adjustable neutral density filter system for dynamic range compression from scene to imaging sensor | |
KR100827238B1 (en) | Apparatus and method for supporting high quality image | |
US20140267654A1 (en) | Comprehensive fixed pattern noise cancellation | |
US7612802B2 (en) | Calibration pixels for image sensor | |
WO2004102956A1 (en) | Digital photography device having a rolling shutter | |
JP2001148808A (en) | Solid-state image pickup device and solid-state image pickup element | |
CN102783135A (en) | Method and apparatus for providing a high resolution image using low resolution | |
US10386632B2 (en) | Lens, camera, package inspection system and image processing method | |
US20090159685A1 (en) | Optimizing Optical Quality of a Sensor in a Bar Code Reader | |
JP2005191748A (en) | Imaging apparatus | |
CN106550197B (en) | The incident light on an imaging sensor of modulation | |
JP2002305682A (en) | Electronic camera and image processing system | |
JPH118803A (en) | Camera having solid-state image pickup device for image receiving | |
JP2017038311A (en) | Solid-state imaging device | |
JP2019140696A (en) | Solid-state imaging device | |
JP2021034852A (en) | Camera device | |
JP3187820B2 (en) | Imaging device | |
JP2002271688A (en) | Television camera | |
JP2011160133A (en) | Wide dynamic range imaging apparatus | |
RU2264047C2 (en) | Camera with two-contour system for adaptation to changes of lighting conditions |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
WWE | Wipo information: entry into national phase |
Ref document number: 200680005790.6 Country of ref document: CN |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application | ||
REEP | Request for entry into the european phase |
Ref document number: 2006719838 Country of ref document: EP |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2006719838 Country of ref document: EP |