# US 8,464,951 B2 · Method and apparatus for monitoring an exit window of a scanner > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,464,951 B2 - Document ID: US8464951B2 - Status: Granted - Kind: B2 - Application number: 12/608,630 - Filed: 2009-10-29 - Published: 2011-05-05 - Granted: 2013-06-18 - Earliest claimed: 2009-10-29 - Assignees: Symbol Technologies, Inc. - Applicants: Miroslav Trajkovic; Jade Zhang - Inventors: Miroslav Trajkovic; Jade Zhang - Web page: https://patentgrep.com/patent/US8464951B2 ## CPC - G06K 7/10: by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation - H04N 1/00013: {Reading apparatus} - H04N 1/00029: {Diagnosis, i.e. identifying a problem by comparison with a normal state} - H04N 1/00037: {Detecting, i.e. determining the occurrence of a predetermined state (H04N1/00031 takes precedence)} - H04N 1/00053: {out of service, i.e. outside of normal operation} - H04N 1/00058: {using a separate apparatus} - H04N 1/00068: {Calculating or estimating} - H04N 1/00076: {locally} - G06K: GRAPHICAL DATA READING (image or video recognition or understanding G06V); PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION ## Abstract A method, system, and apparatus for monitoring an exit window of a scanner using a plurality of imaging devices. The method includes capturing a first image through the exit window using a first imaging device, capturing a second image through the exit window using a second different imaging device, and detecting at least one of a plurality of features in both the first and second images. The method further includes matching the plurality of features detected in both the first and the second images, determining whether the at least one matched feature is present on the plane of the exit window, and monitoring a physical condition of the exit window based on the at least one feature. ## Claims ### Claim 1 A method for monitoring an exit window of a scanner using a plurality of imaging devices located within the scanner, wherein position of the plurality of imaging devices and a plane of the exit window are known, the method comprising: capturing a first image of the exit window using a first imaging device; capturing a second image of the exit window using a second different imaging device; detecting at least one of a plurality of features adversely affecting the performance of the scanner, in both the first and second images; monitoring a physical condition of the exit window based on the at least one detected feature; matching the features detected in both the first and the second images; determining whether at least one matched feature is present on the exit window, wherein the at least one matched feature is present on the exit window when the distance between the at least one matched feature and the exit window is essentially zero; and sending an indication based on the determination. ### Claim 2 (depends on 1) The method of claim 1 further comprising: comparing the number of features present on the exit window plane with a first and second predetermined threshold levels; sending an indication to clean the exit window when the number exceeds a first predetermined threshold level and is below the second predetermined threshold level; and sending an indication to replace the exit window when the number exceeds both the first and second predetermined threshold levels. ### Claim 3 (depends on 1) The method of claim 1 further comprising: comparing an area occupied by the at least one of the plurality of features present on the exit window plane with a first and second predetermined threshold levels; sending an indication to clean the exit window when the area occupied exceeds a first predetermined threshold level and is below the second predetermined threshold level; and sending an indication to replace the exit window when the area occupied exceeds both the first and second predetermined threshold levels. ### Claim 4 (depends on 1) The method of claim 1 further comprising: capturing the image of the exit window when the scanner is in an idle state. ### Claim 5 (depends on 1) The method of claim 1, wherein the exit window is in a field of view (FOV) of at least two of the plurality of imaging devices. ### Claim 6 (depends on 1) The method of claim 1, wherein the scanner is a bi-optic scanner, wherein the exit window is at least one of a horizontal exit window and a vertical exit window of the bi-optic scanner. ### Claim 7 A system for monitoring an exit window of a scanner using a plurality of imaging devices located within the scanner, wherein location of the plurality of imaging devices and a plane of the exit window are known, the system comprising: a scanner; a plurality of imaging devices, wherein a first imaging device captures a first image of the exit window and a second different imaging device captures a second image of the exit window; a processor coupled to the plurality of imaging devices, wherein the processor is configured to, detect at least one of a plurality of features adversely affecting the performance of the scanner, in both the first and second images and monitor a physical condition of the exit window based on the at least one detected feature; and match the features detected in both the first and the second images; and determine whether at least one matched feature is present on the exit window, wherein the at least one matched feature is present on the exit window when the distance between the at least one matched feature and the exit window is essentially zero; and send an indication based on the determination. ### Claim 8 (depends on 7) The system of claim 7, wherein the processor is further configured to: compare a number of features on the exit window plane with a first and second predetermined threshold levels; send an indication to clean the exit window when the number exceeds a first predetermined threshold level and is below the second predetermined threshold level; and send an indication to replace the exit window when the number exceeds both the first and second predetermined threshold levels. ### Claim 9 (depends on 7) The system of claim 7, wherein the processor is further configured to: compare an area occupied by the feature on the exit window plane with a first and second predetermined threshold levels; send an indication to clean the exit window when the area occupied exceeds a first predetermined threshold level and is below the second predetermined threshold level; and send an indication to replace the exit window when the area occupied exceeds both the first and second predetermined threshold levels. ### Claim 10 (depends on 7) The system of claim 7, wherein the exit window is in a field of view (FOV) of at least two of the plurality of imaging devices. ### Claim 11 (depends on 7) The system of claim 7, wherein the scanner is a bi-optic scanner, wherein the exit window is at least one of a horizontal exit window and a vertical exit window of the bi-optic scanner.