JPH01179565A - Illuminating device in picture reader - Google Patents

Abstract

PURPOSE:To obtain a temperature not degrade a characteristic for a color reading by providing a flexible heater to the outer circumference surface of a fluorescent lamp with being adhered and remaining an illuminating window along a length-wise direction. CONSTITUTION:Even when a fluorescent lamp 6 is activated in a cool condition, a temperature sensor 11 detects the temperature of the outer surface of the fluorescent lamp 6 and since a welding is executed to a flexible sheet heater 10 on the basis of detected data, the temperature of the outer circumference surface of the fluorescent lamp 6 speedily rises up to an operating temperature to be set in advance. Thus, a rising time goes to be short and stable operation not to generate the light of a >=650nm wavelength which gives a bad influence to the characteristics of a color filter and a CCD, is obtained. Further, since a heating is forcibly executed by the flexible sheet heater 10, temperature control without the influence of a using environment can be easily executed.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an illumination device in an image reading device that reads color images.

2. Description of the Related Art Generally, in this type of image reading device, a fluorescent lamp is used as a light source, and a CCD and a color filter are used as a sensor section. Due to the characteristics of fluorescent lamps, color filters, and CCDs, light with a wavelength of 650 nm or more degrades reading accuracy. Therefore, conventionally these 6
An infrared filter is provided between the light source and the sensor section to cut out light of 50 nm or more.

Furthermore, when a cold fluorescent lamp is turned on, the heat generated by the fluorescent lamp itself is used to raise the temperature to a point where the characteristics of the fluorescent lamp become stable.

Problems to be Solved by the Invention In order to raise the temperature of a fluorescent lamp to a stable temperature, it takes a long time to stabilize from the time it starts up, and even after stabilization, it may be difficult to read a color image depending on the temperature of the tube surface. Light of 650 nm or more may be generated which reduces the accuracy of the process. Further, there is a problem in that the temperature of the tube surface is not constant over the entire tube surface, and the characteristics vary greatly due to temperature changes.

Means for Solving the Problems In an image reading device that reads color images and is equipped with a sensor section consisting of a CCD and a color filter, and a light source using a fluorescent lamp, an illumination window is provided along the outer peripheral surface of the fluorescent lamp in the longitudinal direction. A flexible seat heater was installed in close contact with the seat.

In addition, a flexible sheet heater was provided, leaving an illumination window that provided the same amount of light throughout from the center to the ends of the fluorescent lamp.

Furthermore, flexible seat heaters were provided which were divided in the longitudinal direction and each independently connected to a control section.

By heating the fluorescent lamp from the outside with a flexible sheet heater, the tube surface temperature of the fluorescent lamp rapidly rises to a stable temperature, and the temperature setting does not deteriorate the characteristics for color reading. It is also possible to obtain a shading effect using a flexible sheet heater, and furthermore, by dividing the flexible sheet heater in the longitudinal direction, it is possible to make the temperature uniform throughout the length of the fluorescent lamp. It is.

Embodiment A first embodiment of the present invention will be explained based on FIGS. 1 to 3. First, in the image reading device 1, a document 3 is placed on the upper surface of a main body case 2, and a guide rail 4 is disposed horizontally inside the main body case 2. A reading unit 5 is connected to a drive device (not shown) and is mounted so as to be able to reciprocate.

A fluorescent lamp 6 as a light source is provided inside the reading unit 5 and is installed long in the reading scanning direction of the original 3, and a sensor section is configured at a position to receive reflected light from the fluorescent lamp 6. A color filter 7 and a CCD 8 are provided.

Next, a flexible sheet heater 1o is provided in close contact with the outer peripheral surface of the fluorescent lamp 6, leaving an illumination window 9 open in the longitudinal direction in the form of a slit. Further, a temperature sensor 11 is provided at the center of the fluorescent lamp 6. The temperature sensor 11 and the flexible seat heater 1o are connected to a control section 12 provided on the bottom surface of the main body case 2.

In such a configuration, even if the fluorescent lamp 6 is started in a cold state, the temperature sensor 11 detects the temperature of the outer surface of the fluorescent lamp 6, and energizes the flexible sheet heater 10 based on that data, so that the fluorescent lamp 6 is started in a cold state. The temperature of the outer peripheral surface of the lamp 6 rapidly rises to the preset operating temperature. As a result, the rise time is short, and stable operation is obtained in which light having a wavelength of 650 nm or more that adversely affects the characteristics of the color filter 7 and the CCD 8 is not generated.

Furthermore, since the flexible sheet heater 10 is forcibly heated, temperature control without being affected by the usage environment can be easily performed.

Next, a second embodiment of the present invention will be described based on FIG. The same parts as in the previous embodiment are denoted by the same reference numerals, and the description thereof will be omitted. In this embodiment, the opening degree of the illumination window 9 by the flexible sheet heater 10 closely formed on the outer peripheral surface of the fluorescent lamp 6 is formed so that the center part is narrow and the end part is wide. This ensures that an even amount of light can be obtained over the entire area. That is, the illumination window 9 has a shading effect, and the entire width of the document 3 is uniformly illuminated.

Further, a third embodiment of the present invention will be described based on FIG. In this embodiment, the flexible seat heater 10 is divided into three parts in the longitudinal direction of the fluorescent lamp 6, and each flexible seat heater 10a, 10b, 10c is independently connected to the control unit 12 so that the temperature can be controlled independently. This is what I did. Therefore, even if there are variations in the characteristics of the fluorescent lamps 6, each flexible sheet heater '310 a, l
Ob, l It can be adjusted as appropriate by controlling the energization to OC.

Effects of the Invention As described above, the present invention provides an image reading device that reads a color image and includes a sensor section including a CCD and a color filter, and a light source using a fluorescent lamp. By leaving the lighting window open and installing the flexible sheet heater in close contact with it, the fluorescent lamp can be heated from outside by the flexible sheet heater.
The tube surface temperature of the fluorescent lamp rapidly rises to a stable temperature, but the temperature setting can be made to a temperature that does not deteriorate the characteristics for color reading, and the central part of the fluorescent lamp Since the flexible sheet heater is installed leaving an illumination window that provides the same amount of light throughout from the end to the end, it is possible to obtain a shading effect with the flexible sheet heater.Furthermore, the flexible sheet heater can be divided in the longitudinal direction and each can be controlled independently. Since a flexible sheet heater connected to the fluorescent lamp is provided, it is possible to maintain a uniform temperature over the entire length of the fluorescent lamp.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing a first embodiment of the present invention, FIG. 2 is a side view thereof, FIG. 3 is a vertical side view of the image copying apparatus, and FIG.
The figure is a perspective view showing a second embodiment of the invention, and FIG. 5 is an explanatory view showing a third embodiment of the invention. DESCRIPTION OF SYMBOLS 1... Image reading device, 6... Fluorescent lamp, 7... Color filter, 8... C, CD, 9... Illumination window, 10
...Flexible seat heater, 12...Control unit ratio Request person Tokyo Electric Co., Ltd. J3.3 diagram, IZ

Claims (1)

[Scope of Claims] 1. In an image reading device that reads a color image and includes a sensor unit including a CCD and a color filter, and a light source using a fluorescent lamp, an illumination window extending along the outer peripheral surface of the fluorescent lamp in the longitudinal direction; 1. An illumination device for an image reading device, characterized in that a flexible sheet heater is provided in close contact with a flexible sheet heater. 2. An illumination device for an image reading apparatus according to claim 1, wherein the flexible sheet heater is provided leaving an illumination window that provides an overall equal amount of light from the center to the end of the fluorescent lamp. 3. An illumination device for an image reading apparatus according to claim 1, further comprising flexible sheet heaters that are divided in the longitudinal direction and each independently connected to the control section.