JPH048696Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an image processing apparatus that eliminates image disturbance at the leading edge of a document.

2. Description of the Related Art Various image recording methods have been known in the past, and one of them is an image recording apparatus that optically reads a document image, converts it into an electrical signal, and then performs signal processing to record the image. In this type of image recording apparatus, optical image information obtained by optically scanning a document is converted into an electrical signal by a photoelectric conversion element, and is extracted as an image signal of time-series image information of a predetermined period. Recently, solid-state image sensors have attracted attention as photoelectric conversion devices used in such applications, and among them,
CCDs (charge-coupled devices) are becoming increasingly popular.

By the way, a CCD has a large number of pixel elements arranged in a horizontal and vertical plane or in a direction perpendicular to the direction of document movement, and each pixel element has the ability to accumulate electric charge according to the intensity of the light irradiated with it. However, when exposed to excessive light, a so-called "charge overflow" phenomenon occurs in which the charge storage ability is lost. When charge overflow occurs, the image information does not become a faithful image signal, and the quality of the recorded image deteriorates. Now, in an image recording device, the original image reading unit is generally the first one.
As shown in the figure, a cross-section taken in the document movement direction is arranged near the end of the document placement section in the document movement direction so that the edge region of the document can be scanned. An optical fiber 4 guides the light from the light emitting body 1 to a document 3 placed on a document glass 2 serving as a document placement section constituting a document table.
, a lens array 5 that receives reflected light (optical information) from the original 3, and an optical sensor array 6 such as a CCD that converts the optical information derived from the lens array 5 into an electrical signal. Luminous body 1,
The optical fiber 4, lens array 5, and sensor array 6 have their longitudinal directions perpendicular to the plane of FIG.

The original glass 2 is held at the end by the frame 7, but as described above, the original image reading unit is located relatively near the end of the original placing section, and the original glass 2 is held at the end by the frame 7. Reflected light from the outside of the document glass 2, that is, from the lower surface of the frame 7, may be input to the optical sensor array 6 due to variations in reading timing or the like.
Conventionally, since the back side of the frame 7 is often white, strong reflected light enters the photosensor array 6 from here, causing the problem of "charge overflow", that is, the charge generated in the CCD due to reflection from the frame 7 is There is a problem in that it remains even after a while, making it impossible to record a faithful image.

Therefore, in the present invention, at least the back side of the frame, which serves as a holding member that fixes and holds the original glass around the periphery, in the direction of movement (direction of the arrow in Figure 1) has a reflectance smaller than the reflectance of the background of the original. Specifically, it is painted gray or a chromatic color.

In this way, even if reflected light from the back side of the frame 7 were to enter the optical sensor array 6 due to disturbances in the movement of the original glass, the intensity of the reflected light would not be so large that the optical sensor array 6 would be There is no need to worry about charge overflow in the component CCD, and there will be no negative effects such as no image appearing or a decrease in contrast at the edges of the document. Furthermore, by making the lower surface of the frame 7 in the direction of movement of the frame 7 as well as the lower surface of the frame 7 in the vertical direction (longitudinal direction of the CCD) similarly low in reflectance, the reflection from the lower surface of the frame 7 in the longitudinal direction of the CCD is reduced. It is even better to prevent the light from reaching the image reading area.

As explained above, the present invention provides an image processing apparatus that performs image processing by optically scanning an original image and converting optical image information obtained by optically scanning the original image into an electrical signal using a photoelectric conversion element. Since the reflection on the photoelectric conversion element on the back side of the periphery of the placing section is made lower than the background of the original, the intensity of the reflected light from the periphery of the original glass is suppressed, and the photoelectric conversion element loses its photoelectric conversion ability. Therefore, it is possible to record without causing any image disturbance at the leading edge of the document.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of the vicinity of the optical scanning position of the image processing apparatus according to the present invention. 1... Light emitter, 2... Original glass, 3... Original, 4... Optical fiber, 5... Lens array,
6... Optical sensor array, 7... Frame.

Claims (1)

[Scope of utility model registration request] A light-transmissive document placement section on which a document is placed, a holding member provided around the document placement section and holding the document placement section, and a support member for holding the document placement section and the document placement section. In the image processing apparatus, the image processing apparatus includes a light source that is provided on the lower side and that irradiates the original with light through the original document placement section, and a photoelectric conversion element that converts the light from the light source into an electrical signal, the lower surface of the holding member. An image processing device characterized in that the reflectance of the image is lower than the reflectance of the background of a document.