US5572006A
Expired / Lapsed
US
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Automatic exposure single frame imaging systems
Assignee: Symbol Technologies LLC
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Filing: 1994-07-26
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Granted: 1996-11-05
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Expires: 2014-07-26
Abstract
Abstract An automatic exposure imaging system operating on a single frame image capture basis is adapted for single chip CMOS type construction. For reading dataforms, such as two-dimensional bar codes and matrix codes, the system can provide automatic gain control, automatic exposure control, automatic focus sensing and single frame imaging and decoding, with reduced power consumption. A fixed focus distance sensor element array assembly and optical distance sensing enable automatic initiation of exposure when the image is in-focus. Exposure provided by image illuminators is automatically controlled by sensing of the cumulative level of reflected light during the exposure period. Alternatively, exposure time is determined from a look-up table, based upon the level of light reflected during an initial illumination period of fixed duration. Automatic system turn-off or re-reading can be provided, depending upon whether a dataform is successfully decoded. Power use is reduced by terminating the reading of sensor elements upon successful decoding. A complete, light-weight, hand-held reader is described, including provision for transmission of decoded dataform information and a wide range of additional capabilities via plug-in cards. Related methods are also described.
Inventors
- 👤 Ynjiun P. Wang
- 👤 Paul P. Ju
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 06:57
CPC Classifications
G; G06; G06K; G06K7/00; G06K7/10; G06K7/10544; G06K7/10821; G06K7/1092; G06K7/10554; G06K7/10564; G06K7/10712; G06K7/10722; G06K7/10752; G06K7/10851
Claims Analysis
Total Claims: 67
Claim 1
Independent Claim
368 words
An automatic exposure imaging system, usable as a dataform reader to read a dataform in a target area at a distance from said reader, comprising: a plurality of sensor elements which are readable to provide image signals and at least some of which are positioned in a two-dimensional array; at least one focus illuminator arranged to illuminate said target area with an area of illumination characterized by at least one of a size, a brightness and a location which varies with the distance between the array and the target area; a user trigger device arranged to activate said at least one focus illuminator and initiate reading of selected sensor elements; an in-focus sensing device responsive to image signals from at least one of said sensor elements and arranged to provide an in-focus signal when said area of illumination is characterized by at least one of a size within a predetermined size range, a brightness within a predetermined brightness range and a location within a predetermined location range; a gain control device responsive, in a period after said in-focus signal, to the level of reflected light as represented by image signals from at least one of said sensor elements and arranged to control image signal amplification; an exposure control device, responsive to image signals from at least one of said sensor elements, and arranged to provide a start signal in response to said in-focus signal and a stop signal in response to reflection of a predetermined level of illumination from said target area; at least one exposure illuminator responsive to said start signal and to said stop signal, and arranged to illuminate said target area during an exposure period determined by said start and stop signals; a memory unit coupled to said array and arranged to store image data representative of said image signals; a processing unit coupled to said memory unit and arranged to process stored image data to decode said dataform, and to provide an end-cycle signal effective to terminate reading of selected sensor elements and operation of the dataform reader, upon successful decoding of the dataform; and an output device coupled to said processing unit and arranged to provide output signals representative of decoded dataform information.
Claim 2
Dependent Claim
368 words
An automatic exposure imaging system, usable as a dataform reader to read a dataform in a target area at a distance from said reader, comprising: a plurality of sensor elements which are readable to provide image signals and at least some of which are positioned in a two-dimensional array; at least one focus illuminator arranged to illuminate said target area with an area of illumination characterized by at least one of a size, a brightness and a location which varies with the distance between the array and the target area; a user trigger device arranged to activate said at least one focus illuminator and initiate reading of selected sensor elements; an in-focus sensing device responsive to image signals from at least one of said sensor elements and arranged to provide an in-focus signal when said area of illumination is characterized by at least one of a size within a predetermined size range, a brightness within a predetermined brightness range and a location within a predetermined location range; a gain control device responsive, in a period after said in-focus signal, to the level of reflected light as represented by image signals from at least one of said sensor elements and arranged to control image signal amplification; an exposure control device, responsive to image signals from at least one of said sensor elements, and arranged to provide a start signal in response to said in-focus signal and a stop signal in response to reflection of a predetermined level of illumination from said target area; at least one exposure illuminator responsive to said start signal and to said stop signal, and arranged to illuminate said target area during an exposure period determined by said start and stop signals; a memory unit coupled to said array and arranged to store image data representative of said image signals; a processing unit coupled to said memory unit and arranged to process stored image data to decode said dataform, and to provide an end-cycle signal effective to terminate reading of selected sensor elements and operation of the dataform reader, upon successful decoding of the dataform; and an output device coupled to said processing unit and arranged to provide output signals representative of decoded dataform information.
Claim 3
Dependent Claim
38 words
An imaging system as in claim 1, additionally comprising an optical filter positioned in front of said array, transmissive to illumination from said exposure illuminator and effective to reduce transmission in other portions of the ambient light spectrum.
Claim 4
Dependent Claim
32 words
An imaging system as in claim 1, wherein said gain control device provides a signal used to control the gain of image signals provided from sensor elements included in said two-dimensional array.
Claim 5
Dependent Claim
43 words
An imaging system as in claim 1, wherein said at least one focus illuminator comprises two focus illuminators providing respective beams of light which intersect in front of the array at a focus distance representative of a fixed focus plane of said array.
Claim 6
Dependent Claim
42 words
An imaging system as in claim 4, additionally comprising a central focusing lens positioned in front of said array and arranged to provide a plane of focus at said focus distance, with a depth of focus range extending about said focus distance.
Claim 7
Dependent Claim
37 words
An imaging system as in claim 4, wherein said in-focus sensing device is arranged to sense at least a predetermined degree of convergence of the illumination areas provided on said target area by said beams of light.
Claim 8
Dependent Claim
44 words
An imaging system as in claim 1, wherein said at least one exposure illuminator comprises an array of illuminator devices arranged to provide a predetermined level of illumination across the target area when said array and said image are separated by a predetermined distance.
Claim 9
Dependent Claim
25 words
An imaging system as in claim 7, additionally comprising a lens array assembly for providing predetermined focusing of light from said array of illuminating devices.
Claim 10
Dependent Claim
15 words
An imaging system as in claim 7, wherein said illuminator devices are light emitting diodes.
Claim 11
Dependent Claim
41 words
An imaging system as in claim 1, wherein said exposure control device develops a voltage representative of the cumulative value of image signals over a period of time and provides said stop signal when said voltage reaches a predetermined threshold voltage.
Claim 12
Dependent Claim
127 words
An automatic exposure system, comprising: a plurality of sensor elements which are readable to provide image signals representative of reflected illumination and at least some of which are positioned in a two-dimensional array; at least one exposure illuminator including an array of illuminator devices arranged to provide a predetermined level of illumination across a selected target area when said array and said target area are separated by a predetermined distance; and an exposure control device responsive to image signals from at least one of said sensor elements and arranged to provide an exposure stop signal in response to a predetermined level of reflected illumination, said exposure stop signal being utilized to turn off said at least one exposure illuminator, which provides illumination resulting in said reflected illumination.
Claim 13
Dependent Claim
127 words
An automatic exposure system, comprising: a plurality of sensor elements which are readable to provide image signals representative of reflected illumination and at least some of which are positioned in a two-dimensional array; at least one exposure illuminator including an array of illuminator devices arranged to provide a predetermined level of illumination across a selected target area when said array and said target area are separated by a predetermined distance; and an exposure control device responsive to image signals from at least one of said sensor elements and arranged to provide an exposure stop signal in response to a predetermined level of reflected illumination, said exposure stop signal being utilized to turn off said at least one exposure illuminator, which provides illumination resulting in said reflected illumination.
Claim 14
Dependent Claim
35 words
An automatic exposure system as in claim 11, wherein said exposure stop signal is utilized to trigger reading of image data from one of the following: at least one sensor element, and all sensor elements.
Claim 15
Dependent Claim
39 words
An automatic exposure system as in claim 11, additionally comprising an optical filter positioned in front of said array, transmissive to illumination from said exposure illuminator and effective to reduce transmission in other portions of the ambient light spectrum.
Claim 16
Dependent Claim
52 words
An automatic exposure system as in claim 11, wherein said sensor elements are arranged to accumulate charge representative of said reflected illumination and said exposure stop signal is provided by said exposure control device when said charge is accumulated to a predetermined level by said at least one of the sensor elements.
Claim 17
Dependent Claim
33 words
An automatic exposure system as in claim 14, wherein said at least one of the sensor elements is arranged to have a predetermined initial charge accumulation at the start of an exposure period.
Claim 18
Dependent Claim
43 words
An automatic exposure system as in claim 11, wherein said exposure control device develops a voltage representative of the cumulative value of image signals over a period of time and provides said exposure stop signal when said voltage reaches a predetermined threshold voltage.
Claim 19
Dependent Claim
209 words
An automatic exposure imaging system, comprising: a plurality of sensor elements which are readable to provide image signals and at least some of which are positioned in a two-dimensional array; at least one focus illuminator arranged to illuminate a target area with an area of illumination characterized by at least one of a size, a brightness and a location which varies with the distance between the array and the target area; an in-focus sensing device responsive to image signals from at least one of said sensor elements and arranged to provide an in-focus signal when said area of illumination is characterized by at least one of a size within a predetermined size range, a brightness within a predetermined brightness range and a location within a predetermined location range; an exposure control device, responsive to image signals from at least one of said sensor elements, and arranged to provide a start signal in response to said in-focus signal and a stop signal in response to reflection of a predetermined level of illumination from said target area; and at least one exposure illuminator responsive to said start signal and to said stop signal, and arranged to illuminate said target area during an exposure period determined by said start and stop signals.
Claim 20
Dependent Claim
209 words
An automatic exposure imaging system, comprising: a plurality of sensor elements which are readable to provide image signals and at least some of which are positioned in a two-dimensional array; at least one focus illuminator arranged to illuminate a target area with an area of illumination characterized by at least one of a size, a brightness and a location which varies with the distance between the array and the target area; an in-focus sensing device responsive to image signals from at least one of said sensor elements and arranged to provide an in-focus signal when said area of illumination is characterized by at least one of a size within a predetermined size range, a brightness within a predetermined brightness range and a location within a predetermined location range; an exposure control device, responsive to image signals from at least one of said sensor elements, and arranged to provide a start signal in response to said in-focus signal and a stop signal in response to reflection of a predetermined level of illumination from said target area; and at least one exposure illuminator responsive to said start signal and to said stop signal, and arranged to illuminate said target area during an exposure period determined by said start and stop signals.
Claim 21
Dependent Claim
38 words
An imaging system as in claim 17, additionally comprising an optical filter positioned in front of said array, transmissive to illumination from said exposure illuminator and effective to reduce transmission in other portions of the ambient light spectrum.
Claim 22
Dependent Claim
43 words
An imaging system as in claim 17, wherein said at least one focus illuminator comprises two focus illuminators providing respective beams of light which intersect in front of the array at a focus distance representative of a fixed focus plane of said array.
Claim 23
Dependent Claim
42 words
An imaging system as in claim 19, additionally comprising a central focusing lens positioned in front of said array and arranged to provide a plane of focus at said focus distance, with a depth of focus range extending about said focus distance.
Claim 24
Dependent Claim
37 words
An imaging system as in claim 19, wherein said in-focus sensing device is arranged to sense at least a predetermined degree of convergence of the illumination areas provided on said target area by said beams of light.
Claim 25
Dependent Claim
44 words
An imaging system as in claim 17, wherein said at least one exposure illuminator comprises an array of illuminator devices arranged to provide a predetermined level of illumination across the target area when said array and said image are separated by a predetermined distance.
Claim 26
Dependent Claim
25 words
An imaging system as in claim 17, additionally comprising a lens array assembly for providing predetermined focusing of light from said array of illuminating devices.
Claim 27
Dependent Claim
15 words
An imaging system as in claim 17, wherein said illuminator devices are light emitting diodes.
Claim 28
Dependent Claim
41 words
An imaging system as in claim 17, wherein said exposure control device develops a voltage representative of the cumulative value of image signals over a period of time and provides said stop signal when said voltage reaches a predetermined threshold voltage.
Claim 29
Dependent Claim
127 words
An imaging system, comprising: a plurality of sensor elements which are readable to provide image signals and at least some of which are positioned in a two-dimensional array; at least one focus illuminator arranged to illuminate a target area with an area of illumination characterized by at least one of a size, a brightness and a location which varies with the distance between the array and the target area; and an in-focus sensing device responsive to image signals from at least one of said sensor elements and arranged to provide an in-focus signal when said area of illumination is characterized by at least one of a size within a predetermined size range, a brightness within a predetermined brightness range and a location within a predetermined location range.
Claim 30
Dependent Claim
127 words
An imaging system, comprising: a plurality of sensor elements which are readable to provide image signals and at least some of which are positioned in a two-dimensional array; at least one focus illuminator arranged to illuminate a target area with an area of illumination characterized by at least one of a size, a brightness and a location which varies with the distance between the array and the target area; and an in-focus sensing device responsive to image signals from at least one of said sensor elements and arranged to provide an in-focus signal when said area of illumination is characterized by at least one of a size within a predetermined size range, a brightness within a predetermined brightness range and a location within a predetermined location range.
Claim 31
Dependent Claim
43 words
An imaging system as in claim 26, wherein said at least one focus illuminator comprises two focus illuminators providing respective beams of light which intersect in front of the array at a focus distance representative of a fixed focus plane of said array.
Claim 32
Dependent Claim
42 words
An imaging system as in claim 26, additionally comprising a central focusing lens positioned in front of said array and arranged to provide a plane of focus at said focus distance, with a depth of focus range extending about said focus distance.
Claim 33
Dependent Claim
37 words
An imaging system as in claim 26, wherein said in-focus sensing device is arranged to sense at least a predetermined degree of convergence of the illumination areas provided on said target area by said beams of light.
Claim 34
Dependent Claim
107 words
An automatic exposure imaging system comprising: a plurality of sensor elements which are readable to provide image signals and at least some of which are positioned in a two-dimensional array; at least one exposure illuminator arranged to illuminate a target area during a preset initial period and during an adjustable exposure period; and an exposure control device responsive to image signals, from at least one of said sensor elements, which are representative of the level of illumination reflected from said target area during said preset initial period, said exposure control device arranged to provide an exposure control signal representative of the duration of said adjustable exposure period.
Claim 35
Dependent Claim
107 words
An automatic exposure imaging system comprising: a plurality of sensor elements which are readable to provide image signals and at least some of which are positioned in a two-dimensional array; at least one exposure illuminator arranged to illuminate a target area during a preset initial period and during an adjustable exposure period; and an exposure control device responsive to image signals, from at least one of said sensor elements, which are representative of the level of illumination reflected from said target area during said preset initial period, said exposure control device arranged to provide an exposure control signal representative of the duration of said adjustable exposure period.
Claim 36
Dependent Claim
159 words
An automatic exposure imaging system comprising: a plurality of sensor elements which are readable to provide image signals and at least some of which are positioned in a two-dimensional array; at least one exposure illuminator arranged to illuminate a target area during a preset initial period and during an adjustable exposure period; an exposure control device responsive to image signals, from at least one of said sensor elements, which are representative of the level of illumination reflected from said target area during said preset initial period, said exposure control device arranged to provide an exposure control signal representative of the duration of said adjustable exposure period; a memory unit arranged to store a look-up table of exposure periods correlated to exposure control signal value; and a processing unit coupled to said exposure control device and said memory unit and responsive to said exposure control signal to utilize said look-up table to determine the duration of said adjustable exposure period.
Claim 37
Dependent Claim
159 words
An automatic exposure imaging system comprising: a plurality of sensor elements which are readable to provide image signals and at least some of which are positioned in a two-dimensional array; at least one exposure illuminator arranged to illuminate a target area during a preset initial period and during an adjustable exposure period; an exposure control device responsive to image signals, from at least one of said sensor elements, which are representative of the level of illumination reflected from said target area during said preset initial period, said exposure control device arranged to provide an exposure control signal representative of the duration of said adjustable exposure period; a memory unit arranged to store a look-up table of exposure periods correlated to exposure control signal value; and a processing unit coupled to said exposure control device and said memory unit and responsive to said exposure control signal to utilize said look-up table to determine the duration of said adjustable exposure period.
Claim 38
Dependent Claim
48 words
An automatic exposure imaging system as in claim 30, wherein said at least one exposure illuminator includes a plurality of illuminators at least one of which is turned on during said preset initial period and at least one of which is turned on during said adjustable exposure period.
Claim 39
Dependent Claim
142 words
An automatic exposure imaging system comprising: a plurality of sensor elements which are readable to provide image signals and at least some of which are positioned in a two-dimensional array; at least one exposure illuminator arranged to illuminate a target area during a preset initial period and during an adjustable exposure period; and an exposure control device responsive to image signals, from two rows of said sensor elements positioned in said two-dimensional array, which are representative of the level of illumination reflected from said target area during said preset initial period, said exposure control device arranged to provide an exposure control signal representative of the duration of said adjustable exposure period; said exposure control device arranged to determine said level of illumination by summing the pixel values represented by image signals from all sensors included in said two rows of sensor elements.
Claim 40
Dependent Claim
142 words
An automatic exposure imaging system comprising: a plurality of sensor elements which are readable to provide image signals and at least some of which are positioned in a two-dimensional array; at least one exposure illuminator arranged to illuminate a target area during a preset initial period and during an adjustable exposure period; and an exposure control device responsive to image signals, from two rows of said sensor elements positioned in said two-dimensional array, which are representative of the level of illumination reflected from said target area during said preset initial period, said exposure control device arranged to provide an exposure control signal representative of the duration of said adjustable exposure period; said exposure control device arranged to determine said level of illumination by summing the pixel values represented by image signals from all sensors included in said two rows of sensor elements.
Claim 41
Dependent Claim
36 words
An automatic exposure imaging system as in claim 31, wherein said sensor elements include charge storage devices which, under the control of said processing unit, are discharged prior to the start of said adjustable exposure period.
Claim 42
Dependent Claim
48 words
An automatic exposure imaging system as in claim 34, wherein, under the control of said processing unit, said at least one exposure illuminator is first turned on for said preset initial period and subsequently turned on for said adjustable exposure period after said charge storage devices are discharged.
Claim 43
Dependent Claim
37 words
An automatic exposure imaging system as in claim 35, wherein image data representative of image signals sensed by said sensor elements during said adjustable exposure period is coupled to said memory unit in preparation for further processing.
Claim 44
Dependent Claim
217 words
An automatic exposure imaging system comprising: a plurality of sensor elements which are readable to provide image signals and at least some of which are positioned in a two-dimensional array; at least one exposure illuminator arranged to illuminate a target area during a preset initial period and during an adjustable exposure period; an exposure control device responsive to image signals, from at least one of said sensor elements, which are representative of the level of illumination reflected from said target area during said preset initial period, said exposure control device arranged to provide an exposure control signal representative of the duration of said adjustable exposure period; at least one focus illuminator arranged to illuminate a target area with an area of illumination characterized by at least one of a size, a brightness and location which varies with the distance between the array and the target area; and an in-focus sensing device responsive to image signals from at least one of said sensor elements and arranged to provide an in-focus signal effective to initiate said preset initial period of illumination by said exposure illuminator when said area of illumination is characterized by at least one of a size within a predetermined size range, a brightness with a predetermined brightness range and a location within a predetermined location range.
Claim 45
Dependent Claim
217 words
An automatic exposure imaging system comprising: a plurality of sensor elements which are readable to provide image signals and at least some of which are positioned in a two-dimensional array; at least one exposure illuminator arranged to illuminate a target area during a preset initial period and during an adjustable exposure period; an exposure control device responsive to image signals, from at least one of said sensor elements, which are representative of the level of illumination reflected from said target area during said preset initial period, said exposure control device arranged to provide an exposure control signal representative of the duration of said adjustable exposure period; at least one focus illuminator arranged to illuminate a target area with an area of illumination characterized by at least one of a size, a brightness and location which varies with the distance between the array and the target area; and an in-focus sensing device responsive to image signals from at least one of said sensor elements and arranged to provide an in-focus signal effective to initiate said preset initial period of illumination by said exposure illuminator when said area of illumination is characterized by at least one of a size within a predetermined size range, a brightness with a predetermined brightness range and a location within a predetermined location range.
Claim 46
Dependent Claim
42 words
An automatic exposure imaging system as in claim 30, additionally comprising a gain control device responsive to the level of reflected light as represented by image signals from at least one of said sensor elements and arranged to control image signal amplification.
Claim 47
Dependent Claim
183 words
An imaging method, for use with an imaging system including an array of sensor elements, comprising the following steps: (a) illuminating a target area with an area of illumination characterized by at least one of a size, a brightness and a location which varies with the distance between the array and the target area; (b) adjusting said distance to cause said area of illumination to be characterized by at least one of a size within a predetermined size range, a brightness within a predetermined brightness range and a location within a predetermined location range; (c) providing an in-focus signal when an image signal from at least one sensor element indicates that said area of illumination is characterized as described in step (b); (d) turning on an exposure illuminator in response to said in-focus signal; (e) providing a stop signal when image signals from at least one sensor element indicate reflection of a predetermined level of illumination from said target area; (f) turning off said exposure illuminator in response to said stop signal; and (g) processing image data from sensor elements of said array.
Claim 48
Dependent Claim
183 words
An imaging method, for use with an imaging system including an array of sensor elements, comprising the following steps: (a) illuminating a target area with an area of illumination characterized by at least one of a size, a brightness and a location which varies with the distance between the array and the target area; (b) adjusting said distance to cause said area of illumination to be characterized by at least one of a size within a predetermined size range, a brightness within a predetermined brightness range and a location within a predetermined location range; (c) providing an in-focus signal when an image signal from at least one sensor element indicates that said area of illumination is characterized as described in step (b); (d) turning on an exposure illuminator in response to said in-focus signal; (e) providing a stop signal when image signals from at least one sensor element indicate reflection of a predetermined level of illumination from said target area; (f) turning off said exposure illuminator in response to said stop signal; and (g) processing image data from sensor elements of said array.
Claim 49
Dependent Claim
35 words
An imaging method as in claim 39, wherein step (a) additionally includes initiating reading of selected sensor elements to provide image signals, and additionally including the following step: (h) terminating reading of selected sensor elements.
Claim 50
Dependent Claim
49 words
An imaging method as in claim 40, wherein step (h) comprises terminating reading of selected sensor elements by causing the termination of at least one of the following: the providing of input power required for such reading, the providing of clock signals required for timing control of such reading.
Claim 51
Dependent Claim
47 words
An imaging method as in claim 39, additionally including an initial step as follows: (x) positioning in front of said array of sensor elements an optical filter transmissive to light from said exposure illuminator and effective to reduce transmission in other portions of the ambient light spectrum.
Claim 52
Dependent Claim
53 words
An imaging method as in claim 39, additionally including an additional step between steps (d) and (e) as follows: (y) utilizing image signals from at least one sensor element, as representative of the level of reflected ambient light, to provide a gain control signal to control amplification of image signals from said array.
Claim 53
Dependent Claim
64 words
An imaging method as in claim 39, wherein step (g) includes processing said image data to decode a dataform included in said target area, and said method includes the additional steps of: (i) providing an end-cycle signal effective to terminate operation of the method upon successful decoding of the dataform; and (ii) coupling the decoded dataform information to an output device for further utilization.
Claim 54
Dependent Claim
42 words
An imaging method as in claim 39, wherein in step (a) said target area is illuminated with an area of illumination comprising spots of illumination provided by two angled light beams which intersect at an in-focus distance in front of the array.
Claim 55
Dependent Claim
34 words
An imaging method as in claim 45, wherein step (b) comprises adjusting said distance to cause said two spots of illumination incident on said target area to merge to at least a predetermined degree.
Claim 56
Dependent Claim
34 words
An imaging method as in claim 46, wherein step (c) comprises providing said in-focus signal when said image signal indicates that said two spots of illumination are merged to at least said predetermined degree.
Claim 57
Dependent Claim
33 words
An imaging method as in claim 39, wherein step (e) comprises providing said stop signal when a voltage developed as representative of the cumulative value of said image signals reaches a threshold value.
Claim 58
Dependent Claim
123 words
An imaging method, for use with an imaging system including an array of sensing elements, comprising the following steps: (a) illuminating a target area with an area of illumination characterized by at least one of a size, a brightness and a location which varies with the distance between the array and the target area; (b) adjusting said distance to cause said area of illumination to be characterized by at least one of a size within a predetermined size range, a brightness within a predetermined brightness range and a location within a predetermined location range; and (c) providing an in-focus signal when an image signal from at least one sensing element indicates that said area of illumination is characterized as described in step (b).
Claim 59
Dependent Claim
123 words
An imaging method, for use with an imaging system including an array of sensing elements, comprising the following steps: (a) illuminating a target area with an area of illumination characterized by at least one of a size, a brightness and a location which varies with the distance between the array and the target area; (b) adjusting said distance to cause said area of illumination to be characterized by at least one of a size within a predetermined size range, a brightness within a predetermined brightness range and a location within a predetermined location range; and (c) providing an in-focus signal when an image signal from at least one sensing element indicates that said area of illumination is characterized as described in step (b).
Claim 60
Dependent Claim
42 words
An imaging method as in claim 49, wherein in step (a) said target area is illuminated with an area of illumination comprising spots of illumination provided by two angled light beams which intersect at an in-focus distance in front of the array.
Claim 61
Dependent Claim
34 words
An imaging method as in claim 50, wherein step (b) comprises adjusting said distance to cause said two spots of illumination incident on said target area to merge to at least a predetermined degree.
Claim 62
Dependent Claim
34 words
An imaging method as in claim 51, wherein step (c) comprises providing said in-focus signal when said image signal indicates that said two spots of illumination are merged to at least said predetermined degree.
Claim 63
Dependent Claim
59 words
An imaging method, for use with an imaging system including an array of sensing elements, comprising the following steps: (a) turning on an exposure illuminator for a preset initial period; (b) determining the level of illumination sensed by at least one sensing element in said preset initial period; and (c) utilizing said level to determine an adjustable exposure period.
Claim 64
Dependent Claim
59 words
An imaging method, for use with an imaging system including an array of sensing elements, comprising the following steps: (a) turning on an exposure illuminator for a preset initial period; (b) determining the level of illumination sensed by at least one sensing element in said preset initial period; and (c) utilizing said level to determine an adjustable exposure period.
Claim 65
Dependent Claim
69 words
An imaging method, for use with an imaging system including an array of sensing elements, comprising the following steps: (a) turning on an exposure illuminator for a preset initial period; (b) determining the level of illumination sensed by at least one sensing element in said preset initial period; and (c) utilizing a look-up table of exposure periods to determine an adjustable exposure period on the basis of said level.
Claim 66
Dependent Claim
69 words
An imaging method, for use with an imaging system including an array of sensing elements, comprising the following steps: (a) turning on an exposure illuminator for a preset initial period; (b) determining the level of illumination sensed by at least one sensing element in said preset initial period; and (c) utilizing a look-up table of exposure periods to determine an adjustable exposure period on the basis of said level.
Claim 67
Dependent Claim
42 words
An imaging method as in claim 54, wherein said look-up table includes a portion usable to provide said adjustable exposure period and a portion usable to provide gain control values for adjusting the gain of image signals provided by said sensing elements.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-11-05 | 2000-05-06 | 2000-11-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-11-05 | 2004-05-06 | 2004-11-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-11-05 | 2008-05-06 | 2008-11-05 | $7700.00 | Window Closed / Lapsed |