Browse Prior Art Database

Charge Coupled Device for Ink Jet Compensation

IP.com Disclosure Number: IPCOM000081290D
Original Publication Date: 1974-May-01
Included in the Prior Art Database: 2005-Feb-27
Document File: 2 page(s) / 50K

Publishing Venue

IBM

Related People

Chai, HD: AUTHOR [+2]

Abstract

This digital-to-analog (D/A) converts digital input data to an analog output signal. The data consists of binary-weighted logic input signals which describe the column position where the drop, if used, is to be printed. This column position information is gated by an Analog Gate and a Data Enable signal line. The Data Enable signal allows the column position information to reach a shift register (S/R) if the drop is to be used for printing, or inhibits the information by clamping the D/A output to ground. The ground potential is required to deflect the drops to a gutter, where they are collected and recirculated in the system.

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Charge Coupled Device for Ink Jet Compensation

This digital-to-analog (D/A) converts digital input data to an analog output signal. The data consists of binary-weighted logic input signals which describe the column position where the drop, if used, is to be printed. This column position information is gated by an Analog Gate and a Data Enable signal line. The Data Enable signal allows the column position information to reach a shift register (S/R) if the drop is to be used for printing, or inhibits the information by clamping the D/A output to ground. The ground potential is required to deflect the drops to a gutter, where they are collected and recirculated in the system.

Before the analog output signal can be applied to the charging electrodes, the signal must first be amplified and compensated. Compensation is required to account for the significant drop interactions, such as the capacitive coupling between the drops during charging.

Compensation is accomplished by storing the analog voltage in a Analog S/R, and every drop formation period shifting the data in sequence from the 3rd output to the 4th, 2nd to 3rd, 1st to 2nd, and input to the 1st. The outputs of each S/R position are connected to an appropriate weighted input summing resistor of an output summing amplifier A. The shifting of the data is controlled by a phase maintenance scheme.

The correct phase relationship between drop separation time and applied charging voltage is maintained by a Gated Ramp...