EP0310702A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Method of operating photo-sensor units
Assignee: Canon Inc
•
Filing: 1987-10-09
•
Granted: —
•
Expires: 2007-10-09
Abstract
Abstract An image reading device has photo-sensor units arranged in the form of an array constituting a line sensor. Each sensor unit includes a light-shielding layer formed on a light-transmitting substrate, an insulating layer formed on the light-shielding layer, a semiconductor layer disposed on the insulating layer, and a pair of upper electrodes provided on the semiconductor layer and spaced from each other, the space between the upper electrodes constituting a light-receiving window through which the semiconductor layer receives light applied from the reverse side of the substrate onto the surface of an image carrying original and reflected by the original, so that the semiconductor layer produces an electric signal representing the read image. The light-shielding layer is made of an electrically conductive material such as a metal. A voltage application means for applying to the light-shielding electrode a voltage of a level which is lower than the levels of voltages applied to the pair of upper electrodes. The levels of the voltage may be varied along the length of the array of the photo-sensor units.
Inventors
- 👤 Satoshi Itabashi
- 👤 Toshihiro Saika
- 👤 Ihachiro Gofuku
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 05:51
CPC Classifications
H; H10; H10F; H10F39/00; H10F39/80; H10F39/805; H10F39/8057; H04; H04N; H04N25/00; H04N25/60; H04N25/63; H04N25/633; H04N25/70; H04N25/701; H10F39/10; H10F39/12; H10F39/191
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
142 words
An image reading device having photo-sensor units each including a light-shielding layer formed on a light-transmitting substrate, an insulating layer formed on said light-shielding layer, a semiconductor layer disposed on said insulating layer, and a pair of upper electrodes provided on said semiconductor layer and spaced from each other, the space between said upper electrodes constituting a light-receiving window through which said semiconductor layer receives light applied from the reverse side of said substrate onto the surface of an image-carrying original and reflected by said original, so that said semiconductor layer produces an electric signal representing the read image, said image reading device comprising: an electrically conductive layer constituting said light-shielding layer; and voltage application means for applying to said light-shielding electrode a voltage of a level which is lower than the levels of voltages applied to said pair of upper electrodes.
Claim 2
Dependent Claim
142 words
An image reading device having photo-sensor units each including a light-shielding layer formed on a light-transmitting substrate, an insulating layer formed on said light-shielding layer, a semiconductor layer disposed on said insulating layer, and a pair of upper electrodes provided on said semiconductor layer and spaced from each other, the space between said upper electrodes constituting a light-receiving window through which said semiconductor layer receives light applied from the reverse side of said substrate onto the surface of an image-carrying original and reflected by said original, so that said semiconductor layer produces an electric signal representing the read image, said image reading device comprising: an electrically conductive layer constituting said light-shielding layer; and voltage application means for applying to said light-shielding electrode a voltage of a level which is lower than the levels of voltages applied to said pair of upper electrodes.
Claim 3
Dependent Claim
40 words
An image reading device according to Claim 1, wherein the level of said voltage applied by said voltage application means is high enough to change said semiconductor layer into a depletion layer over the entire thickness of said semiconductor layer.
Claim 4
Dependent Claim
28 words
An image reading device according to Claim 1, wherein a plurality of said photo-sensor units are arrayed on said substrate so as to constitute a one-dimensional sensor array.
Claim 5
Dependent Claim
197 words
An image reading device having photo-sensor units each including a light-shielding layer formed on a light-transmitting substrate, an insulating layer formed on saidlight-shielding layer, a semiconductor layer disposed on said insulating layer, and a pair of upper electrodes provided on said semiconductor layer and spaced from each other, the space between said upper electrodes constituting a light-receiving window through which said semiconductor layer receives light applied from the reverse side of said substrate onto the surface of an image-carrying original and reflected by said original, so that said semiconductor layer produces an electric signal representing the read image, said image reading device comprising: an electrically conductive layer constituting said light-shielding layer; and voltage application means adapted to apply to said light-shielding layer a bias voltage of a level determined in accordance with the polarity of the carrier carrying the photoelectric current generated in said semiconductor layer and also with the quantity of the charges of said carrier, said voltage application means being further adapted to apply, in the non-reading period of the reading operation, a voltage V a having the same polarity as said bias voltage and an absolute value smaller than that of said bias voltage.
Claim 6
Dependent Claim
197 words
An image reading device having photo-sensor units each including a light-shielding layer formed on a light-transmitting substrate, an insulating layer formed on saidlight-shielding layer, a semiconductor layer disposed on said insulating layer, and a pair of upper electrodes provided on said semiconductor layer and spaced from each other, the space between said upper electrodes constituting a light-receiving window through which said semiconductor layer receives light applied from the reverse side of said substrate onto the surface of an image-carrying original and reflected by said original, so that said semiconductor layer produces an electric signal representing the read image, said image reading device comprising: an electrically conductive layer constituting said light-shielding layer; and voltage application means adapted to apply to said light-shielding layer a bias voltage of a level determined in accordance with the polarity of the carrier carrying the photoelectric current generated in said semiconductor layer and also with the quantity of the charges of said carrier, said voltage application means being further adapted to apply, in the non-reading period of the reading operation, a voltage V a having the same polarity as said bias voltage and an absolute value smaller than that of said bias voltage.
Claim 7
Dependent Claim
31 words
An image reading device according to Claim 4, wherein said voltage V a is applied to said light-shielding layer for a predetermined period immediately before the commencement of the reading operation.
Claim 8
Dependent Claim
85 words
An image reading device having a plurality of photo-sensors arrayed on a substrate and each including an electrically conductive layer, an insulating layer formed on said conductive layer, a semiconductor layer disposed on said insulating layer and a pair of main electrodes provided in contact with said semiconductor layer and spaced from each other, comprising: bias voltage application means for applying a bias voltage to said conductive layer, the level of said bias voltages being varied in the direction of array of said photo-sensor units.
Claim 9
Dependent Claim
85 words
An image reading device having a plurality of photo-sensors arrayed on a substrate and each including an electrically conductive layer, an insulating layer formed on said conductive layer, a semiconductor layer disposed on said insulating layer and a pair of main electrodes provided in contact with said semiconductor layer and spaced from each other, comprising: bias voltage application means for applying a bias voltage to said conductive layer, the level of said bias voltages being varied in the direction of array of said photo-sensor units.
Claim 10
Dependent Claim
26 words
An image reading device according to Claim 6, wherein said photo-sensors are arranged linearly on said substrate in correspondence with the widthwise direction of the original.
Claim 11
Dependent Claim
31 words
An image reading device according to Claim 1, wherein the array of said photo-sensor units has a length corresponding to the width of an original carrying the image to be read.
Claim 12
Dependent Claim
52 words
An image reading device according to Claim 7, wherein the array of said photo-sensor units is grouped into a plurality of blocks each having a predetermined number of said photo-sensor units, said bias voltage application means being designed to apply different levels of biasing voltage to different blocks of said photo-sensor units.
Claim 13
Dependent Claim
67 words
An image reading device according to Claim 6, wherein said substrate is made of a transparent material while said electrically conductive layer, and wherein said semiconductor layer receives, through a window constituted by the space between said pair of main electrodes, the light which is applied from the reverse side of said substrate onto an original carrying an image to be read and reflected by said original.
References Cited (Backward Citations)
EP0232083A1
Cited
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.