Browse Prior Art Database

Light Sensor for Ink Droplets

IP.com Disclosure Number: IPCOM000080748D
Original Publication Date: 1974-Feb-01
Included in the Prior Art Database: 2005-Feb-27
Document File: 2 page(s) / 38K

Publishing Venue

IBM

Related People

Hendee, RC: AUTHOR [+2]

Abstract

Accurate monitoring of droplets in an ink jet stream can be accomplished, by passing the stream of droplets between a light source and matrix of light-sensing devices. The matrix arrangement of detection devices enables observation of droplet behavior in flight, to permit necessary adjustments to charging voltages and nozzle alignment.

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 100% of the total text.

Page 1 of 2

Light Sensor for Ink Droplets

Accurate monitoring of droplets in an ink jet stream can be accomplished, by passing the stream of droplets between a light source and matrix of light-sensing devices. The matrix arrangement of detection devices enables observation of droplet behavior in flight, to permit necessary adjustments to charging voltages and nozzle alignment.

In the figure, a stream of ink droplets 1 passes between a light source 2 and aperture plate 3 having a matrix of holes 4 therein. The holes are of a size and spacing that will prevent droplets from passing undetected. Aperture plate 3 is supported in frame 5 which also holds a corresponding matrix array 6 of light- sensing devices 7, such as diodes. The diodes can be fabricated with small center-to-center distances necessary for the sensing apertures. The diode output levels are then monitored and recorded to provide an indication of the droplet flight path in the jet stream.

1

Page 2 of 2

2

[This page contains 2 pictures or other non-text objects]