Browse Prior Art Database

STEPPED NEUTRAL DENSITY FILTER DIAGNOSTIC TOOL FOR CHANNEL SENSORS

IP.com Disclosure Number: IPCOM000027736D
Original Publication Date: 1999-Apr-30
Included in the Prior Art Database: 2004-Apr-09
Document File: 2 page(s) / 107K

Publishing Venue

Xerox Disclosure Journal

Abstract

Disclosed is a stepped, neutral density filter useable in conjunction with the diagnostic mode of an electrophotographic printing machine to determine the degradation of channel sensors located therein. By using a sensor's known electrical characteristics and relating it to different transmittance levels, a reading can be obtained predicting the sensor's remaining life.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 55% of the total text.

Page 1 of 2

XEROX DISCLOSURE JOURNAL

STEPPED NEUTRAL DENSITY FILTER DIAGNOSTIC TOOL FOR CHANNEL SENSORS Int. C1. G03g 15/00 Salvatore A. Abbata
Edward E. Drexler

Proposed Classification
U. S. C1.3991013

Disclosed is a stepped, neutral density filter useable in conjunction with the diagnostic mode of an electrophotographic printing machine to determine the degradation of channel sensors located therein. By using a sensor's known electrical characteristics and relating it to different transmittance levels, a reading can be obtained predicting the sensor's remaining life.

In the life cycle of a typical channel sensor 10 shown in the accompanying figure, the predominant failure mode is related to a Light Emitting Diode (LED) stage 12 producing

XEROX DISCLOSURE JOURNAL - Vol. 24, No. 2 MarcWApril 1999 69

[This page contains 1 picture or other non-text object]

Page 2 of 2

STEPPED NEUTRAL DENSITY FILTER DIAGNOSTIC TOOL FOR CHANNEL SENSORS (Cont'd)

the required energy to excite a detecting transistor stage 14. Placing a stepped, neutral density filter 16 in a channel forming an optical path separating LED 12 from transistor 14 simulates this degradation. Filter 16 is appropriately marked to indicate various transmittance levels 1, 2, and 3 for visual referencing. One skilled in the art will recognize that filter 16 may have more than the three steps shown in the accompanying figure. The filter's size is approximately 2 inches by 1 inch in size and easily carried. As shown, step 2 of filter 16 attenuates the emitted energy indicated by arrows 18 to a reduced energy indicated by arrows 20. The transmittance level of step 2 controls the amount of atten...