JPH0444460A - Picture input device - Google Patents

Abstract

PURPOSE:To detect the deterioration in a light source quantitatively by providing a picture input section reading a fully white read pattern as an electric signal and receiving the signal as a multi-value digital signal and a control section controlling the picture input section and detecting the deterioration in the light source to apply alarm processing to the picture input device. CONSTITUTION:When a control section 7 outputs a lighting control signal 10 to a light source 2 from an output terminal 7d at first, the light source 2 is lighted. When a photoelectric conversion element drive signal 9 outputted from an output terminal 7c is inputted to a photoelectric conversion element 4, the photoelectric conversion element 4 is active and an electric signal is outputted to an A/D converter circuit 5. After the control section 7 detects a maximum value (MAX) of an output level within an effective read range, the output level is confirmed as to each picture element within the effective read range, and when the picture element below 80% of the maximum value (MAX) is detected, that is, the luminous quantity of the light source 2 is decreased at a left edge A of the read position, it is processed as the deterioration in the light source and alarm processing is implemented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an image processing device such as a facsimile, and more particularly to an image input device equipped with means for detecting deterioration of a light source in an image input section.

[Conventional technology]

Conventionally, this kind of image input device has been designed to use a photoelectric conversion element to convert the dimensional reflected light emitted from a light source onto the original to be read into an electrical signal and input the signal.

[Problem to be solved by the invention]

The conventional image input device described above does not have a means for detecting light source deterioration, so it is necessary to check the image quality of the reproduced image of the input image signal caused by light source deterioration. There is a drawback that sometimes quantitative detection of light source deterioration cannot be performed.

[Elaborate means to solve problems]

The image input device according to the present invention includes an m1re input section that reads an all-white reading pattern as an electric signal and then inputs it as a multi-value digital signal, and controls the image input section and prevents deterioration of the light source by controlling the multi-value image input signal. It has a control i11 section that performs detection and alarm processing.

[For production]

According to the present invention, deterioration of a light source can be easily detected using a multivalued image input signal.

〔Example〕

FIG. 1 is a schematic block diagram showing an embodiment of an image input device according to the present invention. In the figure, reference numeral 1 denotes an all-white reading pattern set in the reading section, a light source that irradiates two all-white reading patterns 1, and 3 a reflection from the all-white reading pattern 1, ft1! 4 is a photoelectric conversion element that receives this reflected light and converts it into an electrical signal; 5 is an A/D conversion circuit that multivalues the output signal of this photoelectric conversion element 4 and outputs a multivalued image input signal 6. , T receives this multivalued image input signal 6 at input terminal T&, and outputs A/T from output terminal 7b.
A D conversion control signal 8 is output, a photoelectric conversion label drive signal 9 is output from the output terminal 7c, a lighting control signal 10 is output from the output terminal 7d, and a multivalued image input signal 6 within the effective reading range is output.
After detecting the maximum value (MAX) of A control unit 11 performs alarm processing when the light source 2 deteriorates. lens 3
．． This is an image input section composed of a photoelectric conversion element 4 and an A/D conversion circuit 5.

Note that A and B indicate the left and right ends of the effective reading position in the reading section where the all-white reading pattern 1 is set. FIG. 2 is an output distribution diagram showing the output level of the multivalued image input signal 6 regarding the all-white reading pattern.

Next, the operation of the image input device having the above configuration will be explained. First, when the control unit T outputs the lighting control signal 10 to the light source 2 from its output terminal 1d, the light source 2 lights up. Prior to the image input operation, reflected light from the all-white reading pattern set in the reading section is input to the photoelectric conversion element 4 via the lens 3. When the photoelectric conversion element drive signal 9 output from the output terminal 7c of the control section 7 is input to the photoelectric conversion element 4, the photoelectric conversion element 4 operates and outputs an electric signal to the A/D conversion circuit 5.

This A/D conversion circuit 5 operates in accordance with the A/D conversion control signal 8 outputted from the output terminal 7b of the control section 7, and multivalues the electric signal inputted from the photoelectric conversion element 4, as shown in FIG. A multivalued image input signal 6 like this is output to the control section 7. For this purpose, the control unit 7 detects the maximum value (MAY) of the output level within the effective reading range, then checks the output level for each pixel within the effective reading range, and then checks the maximum value (MAY) of the output level for each pixel within the effective reading range.
Since it is considered that the light I of the light source 2 is decreasing when 80 pixels or less of MAX) are detected, that is, at the left end A of the reading position, an alarm process can be performed as a result of deterioration of the light source.

〔Effect of the invention〕

As described above in detail, according to the present invention (the image input device), prior to the image input operation, an all-white reading pattern is input as an image signal, and the light intensity distribution characteristics of the light source are confirmed from the input data. By doing so, it is possible to detect deterioration of the light source in a constant I manner.

[Brief explanation of drawings]

FIG. 1 is a schematic block diagram showing an embodiment of an image input device according to the present invention, and FIG. 2 is an output distribution diagram showing the output level of a multi-level one signal regarding an all-white reading pattern. 1...All-white reading pattern, 2...Light source, 3...
...Lens, 4...Photoelectric conversion element. 5...A/D conversion circuit, 6...Multi-value l1fi
e input code, 7...control unit, 8...A/D conversion control signal, 9...photoelectric conversion element drive signal, 10...
...Lighting control signal, 11...Image input section. Patent applicant: NEC Corporation

Claims (1)

[Claims] An image input device that converts reflected light emitted from a light source onto a read document into an electrical signal by a photoelectric conversion element and inputs the converted signal; An image input device characterized by comprising a control section that controls the image input section and detects deterioration of the light source using a multivalued image input signal and performs alarm processing.