Adaptive threshold optical reader
Patent 4230265 Issued on October 28, 1980. Estimated Expiration Date: 
May 7, 1999. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
May 7, 1999. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 3675201 3692983 3778768 3833833 InventorAssigneeApplicationNo. 06/036686 filed on 05/07/1979US Classes:235/455, Light level control235/459, Stationary250/555, Including coded record382/270Variable threshold, gain, or slice levelExaminersPrimary: Cook, Daryl W.Attorney, Agent or FirmInternational ClassesG06K 7/10 (20060101)G06K 7/14 (20060101) AbstractAn adaptive threshold optical reader for detecting optically encoded information when positioned within an optical path, including a light source for producing light energy along the optical path, a light detector responsive to the light energy along the optical path and for producing an ouput signal in accordance with the light energy detected by the light detector, means responsive to the output signal from the light detector and with the means having at least two states and with the means in a first state producing an adaptive threshold signal when there is no optically encoded information positioned within the optical path and with the adaptive threshold signal representative of the output signal from the light detector with a threshold level of optically encoded information and adaptive to optical changes and with the means in a second state for producing an information signal representative of the output signal from the light detector when there is optically encoded information positioned within the optical path, means responsive to the adaptive threshold signal for storing the adaptive threshold signal, and means responsive to the stored adaptive threshold signal and the information signal for detecting the presence of optically encoded information in the information signal above a threshold level in accordance with the stored adaptive threshold signal. | |
