JPH0444770U

JPH0444770U -

Info

Publication number: JPH0444770U
Application number: JP8699390U
Authority: JP
Priority date: 1990-08-22
Filing date: 1990-08-22
Publication date: 1992-04-16

Description

[Brief explanation of drawings]

第１図は本考案の一実施例を示すブロツク図、
第２図は同実施例の信号波形図、第３図乃至第７
図は本考案の他の実施例を示すもので、第３図は
ブロツク図、第４図は第３図におけるラインメモ
リの構成図、第５図は乗算器の構成図、第６図は
比較器の構成図、第７図はブロツク図、第８図は
従来例を示すブロツク図である。１１……ＣＣＤセンサー、１２，１２′……Ａ
／Ｄ変換器、１３……切替スイツチ、１４，１４
′……乗算器、１５，１５′……ラインメモリ、
１６，１６′……比較器、１７，１７′……制御
回路。 FIG. 1 is a block diagram showing an embodiment of the present invention.
Figure 2 is a signal waveform diagram of the same embodiment, Figures 3 to 7
The figures show other embodiments of the present invention, in which Fig. 3 is a block diagram, Fig. 4 is a block diagram of the line memory in Fig. 3, Fig. 5 is a block diagram of a multiplier, and Fig. 6 is a comparison diagram. FIG. 7 is a block diagram, and FIG. 8 is a block diagram showing a conventional example. 11...CCD sensor, 12, 12'...A
/D converter, 13... selector switch, 14, 14
'... Multiplier, 15,15'... Line memory,
16, 16'... Comparator, 17, 17'... Control circuit.

Claims

[Scope of claim for utility model registration] (1) A photoelectric line sensor that reads images;
An analog-to-digital converter converts the photoelectric line sensor output into a digital signal, and digital data from the analog-to-digital converter when the photoelectric line sensor reads the reference white.
(0<n<1); a memory for storing the multiplied contents by the multiplication means; digital data from the analog-to-digital converter when the photoelectric line sensor reads the document; An image signal processing device comprising a comparing means for comparing digital data stored in a memory and outputting a binary image signal. (2) The multiplication means sets a plurality of n values, and each n
Claim (1) characterized in that the value can be selected.
The image signal processing device described. (3) A photoelectric line sensor that reads images;
an analog-to-digital converter that converts the photoelectric line sensor output into a digital signal; and a memory that stores at least one line of digital data from the analog-to-digital converter when the photoelectric line sensor reads the reference white; Compare the digital data from the analog-to-digital converter when the photoelectric line sensor reads the original with the digital data stored in the memory.
The analog-to-digital converter is configured to digitize the input signal with a threshold corresponding to the level difference between two high and low reference signal voltages, and the photoelectric line sensor is configured to output a reference white signal. An image signal processing device characterized in that the level difference between the two reference signal voltages when reading is set to twice the level difference between the two reference signal voltages when the photoelectric line sensor reads the document.