← Back to Patent Explorer
US4794453A Expired / Lapsed US ⏱️ 0.0 years remaining

Method and apparatus for stroboscopic video inspection of an asynchronous event

Assignee: WEB PRINTING CONTROLS Co A CORP OF ILL
•
Filing: 1986-09-09
•
Granted: 1988-12-27
•
Expires: 2006-09-09
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract Apparatus and method particularly suitable for use with the closed loop color to color registration system of a commercial web printing apparatus utilizes a CCD camera having an image sensor and a synchronization generator circuit which generates periodic scan pulses which trigger the image acquisition scan of the image sensor. A predetermined time prior to triggering of a strobe a prefresh pulse is generated in order to trigger a complete scan of the image sensor prior to firing the strobe. A predetermined time period subsequent to the firing of the strobe a scan triggering pulse is generated to trigger an image acquisition scan of the image sensor. This results in highly stable and reliable acquisition of a low noise image of for example, a registration mark on a printed web which may then be processed by a registration control system.

Inventors

  • 👤 Herman C. Gnuechtel
  • 👤 Stephen P. Kosmen

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 14:36
CPC Classifications
H; H04; H04N; H04N7/00; H04N7/18; H04N7/188

Claims Analysis

Total Claims: 24
Claim 1
Independent Claim 130 words
Apparatus for synchronizing high intensity short duration illumination of a substantially predictable asynchronous event in real-time with image acquisition by a video camera having an image sensor and a synchronization generator circuit which generates periodic scan pulses which trigger an image acquisition scan of the image sensor, comprising: means for selectively disabling the periodic scan pulses and for generating a prefresh scan pulse for triggering an image acquisition scan of the image sensor a first predetermined time period prior to the substantially predictable event thereby preconditioning the image sensor and disabling image acquisition scan until occurrence of the substantially predictable event; and means for triggering an image acquisition scan of the image sensor subsequent to the first predetermined time period to generate image data corresponding to the substantially predictable event.
Claim 2
Dependent Claim 130 words
Apparatus for synchronizing high intensity short duration illumination of a substantially predictable asynchronous event in real-time with image acquisition by a video camera having an image sensor and a synchronization generator circuit which generates periodic scan pulses which trigger an image acquisition scan of the image sensor, comprising: means for selectively disabling the periodic scan pulses and for generating a prefresh scan pulse for triggering an image acquisition scan of the image sensor a first predetermined time period prior to the substantially predictable event thereby preconditioning the image sensor and disabling image acquisition scan until occurrence of the substantially predictable event; and means for triggering an image acquisition scan of the image sensor subsequent to the first predetermined time period to generate image data corresponding to the substantially predictable event.
Claim 3
Dependent Claim 45 words
The apparatus of claim 1, further comprising refresh means for generating periodic refresh pulses, and means for disabling the scan pulses generated by the internal synchronization generator circuit and substituting the refresh pulses such that the refresh pulses are utilized as the periodic scan pulses.
Claim 4
Dependent Claim 31 words
The apparatus of claim 1 further comprising means for disabling the means for triggering an image acquisition scan for a second predetermined time period after the high intensity short duration illumination.
Claim 5
Dependent Claim 20 words
The apparatus of claim 1 wherein the substantially predictable event is substantially predictable within a time window of known duration.
Claim 6
Dependent Claim 41 words
The apparatus of claim 1 wherein the substantially predictable event is movement to a location detectable by the video camera of a portion of a printed pattern on a moving web within a web printing apparatus having a known repeat length.
Claim 7
Dependent Claim 20 words
The apparatus of claim 5 wherein the desired portion of the printed pattern on the web is a registration mark.
Claim 8
Dependent Claim 37 words
The appartus of claim 1 further comprising an illuminator means for providing high intensity, short duration illumination to illuminate the substantially predictable event and means for activating the illuminator means in response to the substantially predictable event.
Claim 9
Dependent Claim 45 words
The apparatus of claim 7 further comprising a means for disabling the illuminator means for a period of time immediately after the illuminator is activated, said time period being sufficiently long to prevent the illuminator means from generating interfering signals during the image acquisition scan.
Claim 10
Dependent Claim 14 words
The apparatus of claim 1 further comprising storage means for storing the image data.
Claim 11
Dependent Claim 49 words
The apparatus of claim 1 wherein the means for triggering comprises a precision timing means for generating a precision first predetermined time period such that the high intensity, short duration illumination is triggered to occur the precision first predetermined time period subsequent to generation of the prefresh scan pulse.
Claim 12
Dependent Claim 23 words
The apparatus of claim 1 wherein the first predetermined period is at least as long as the period of the periodic scan pulses.
Claim 13
Dependent Claim 22 words
The apparatus of claim 2 wherein the periodic refresh pulses have a period at least as long as the periodic scan pulses.
Claim 14
Dependent Claim 41 words
The apparatus of claim 1 wherein the first predetermined period is at least long enough to permit an image acquisition scan of a predetermined portion of the image sensor sufficient to provide desired image data corresponding to the substantially predictable event.
Claim 15
Independent Claim 150 words
A method for synchronizing image acquisition by a video camera to high intensity short duration illumination of a substantially predictable asynchronous event in real time wherein the video camera includes an image sensor, the method comprising the steps of; generating periodic refresh pulses to periodically trigger an image acquisition scan of the image sensor; disabling the refresh pulses and generating a prefresh pulse a first predetermined time period prior to the substantially predictable event for triggering an image acquisition scan of the image sensor a first predetermined time period prior to the substantially predictable event thereby preconditioning the image sensor and disabling image acquisition scan until occurrence of the substantially predictable event; and generating an image acquisition pulse for triggering an image acquisition scan of the image sensor a second predetermined time period subsequent to the first predetermined time period to generate image information responsive to the substantially predictable event.
Claim 16
Independent Claim 150 words
A method for synchronizing image acquisition by a video camera to high intensity short duration illumination of a substantially predictable asynchronous event in real time wherein the video camera includes an image sensor, the method comprising the steps of; generating periodic refresh pulses to periodically trigger an image acquisition scan of the image sensor; disabling the refresh pulses and generating a prefresh pulse a first predetermined time period prior to the substantially predictable event for triggering an image acquisition scan of the image sensor a first predetermined time period prior to the substantially predictable event thereby preconditioning the image sensor and disabling image acquisition scan until occurrence of the substantially predictable event; and generating an image acquisition pulse for triggering an image acquisition scan of the image sensor a second predetermined time period subsequent to the first predetermined time period to generate image information responsive to the substantially predictable event.
Claim 17
Dependent Claim 55 words
The method of claim 14 wherein the video camera includes a synchronization generator circuit that generates periodic scan pulses which trigger periodic image acquisition scans of the image sensor, the method further comprising the step of disabling the scan pulses of the synchronization generator circuit and replacing the scan pulses with the periodic refresh pulses.
Claim 18
Dependent Claim 28 words
The method of claim 14 further comprising the step of triggering a short duration, high intensity illumination of the substantially predictable event responsive to the substantially predicable event.
Claim 19
Dependent Claim 40 words
The method of claim 16, wherein an illuminator requiring pre-charging is utilized for providing the short duration, high intensity illumination, further comprising the step of disabling pre-charging of the illuminator for a time period after the triggering of the illumination.
Claim 20
Dependent Claim 14 words
The method of claim 17 further comprising the step of storing the image information.
Claim 21
Dependent Claim 143 words
Apparatus for synchronizing high intensity short duration illumination of a substantially predictable recurring asynchronous event in real-time with image acquisition by a video camera, comprising: a video camera having an image sensor and a synchronization generator circuit which generates periodic scan pulses which trigger image acquisition scans of the image sensor; means for disabling the periodic scan pulses; illumination means for providing high intensity, short duration illumination to illuminate the substantially predictable event; means for activating the illumination means in response to the substantially predictable event including means for pre-charging to enable said activation; means for triggering an image acquisition scan of the image sensor in response to activation of the illumination means to generate image data corresponding to the substantially predictable event; means for disabling the means for pre-charging for a first predetermined period subsequent to the activation of the illumination means.
Claim 22
Dependent Claim 143 words
Apparatus for synchronizing high intensity short duration illumination of a substantially predictable recurring asynchronous event in real-time with image acquisition by a video camera, comprising: a video camera having an image sensor and a synchronization generator circuit which generates periodic scan pulses which trigger image acquisition scans of the image sensor; means for disabling the periodic scan pulses; illumination means for providing high intensity, short duration illumination to illuminate the substantially predictable event; means for activating the illumination means in response to the substantially predictable event including means for pre-charging to enable said activation; means for triggering an image acquisition scan of the image sensor in response to activation of the illumination means to generate image data corresponding to the substantially predictable event; means for disabling the means for pre-charging for a first predetermined period subsequent to the activation of the illumination means.
Claim 23
Dependent Claim 31 words
The apparatus of claim 19 further comprising means for disabling the means for triggering an image acquisition scan for a second predetermined time period after the activation of the illumination means.
Claim 24
Dependent Claim 35 words
The apparatus of claim 20 further comprising means for generating a prefresh scan pulse for triggering an image acquisition scan of the image sensor a third predetermined time period prior to the substantially predictable event.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1991-12-27 1992-06-27 1992-12-27 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1995-12-27 1996-06-27 1996-12-27 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1999-12-27 2000-06-27 2000-12-27 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag