JPS61144964A - Light source device - Google Patents

Abstract

PURPOSE:To eliminate the need for a thermostat, etc., as a control means which controls the heating value of a preheater according to ambient temperature and to improve serviceability and economy by using a self-controlling heating element as the heater for preheating. CONSTITUTION:The self-controlling heating element heater 2 is provided in contact with a fluorescent body 1 at the opposite side of original platen glass 3, and the fluorescent lamp 1 is preheated through feeding electrodes 2a and 2b. The self-controlling heating element whose power consumption is large when the ambient temperature is low and the preheating element needs to have large heating value and small when the ambient temperature is high and the preheater needs not have large heating value is used as the preheater, so temperature control is performed without requiring any other control circuit, so the serviceability and economy are improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a light source device, and relates to preheating for stabilizing the amount of light emitted from, for example, a fluorescent lamp used in an image scanner.

[Background of the invention]

Conventional technology generally involves using a heating wire as a preheater, measuring the tube wall temperature of a fluorescent lamp, and controlling the tube wall temperature. However, this method requires a device to measure the tube wall temperature of the fluorescent lamp, a device to control the amount of heat generated by the electric heater, etc., making it smaller and easier to maintain.

No consideration was given to economic efficiency.

As for the technology related to this rice, #i JP-A No. 52-68
The one disclosed in Japanese Patent No. 410 can be mentioned.

[Purpose of the invention]

An object of the present invention is to provide a light source with excellent maintainability and economical efficiency.

[Summary of the invention]

The present invention uses a self-regulating heating element as a preheating heater, eliminates the need for a thermostat, etc. as a means to control the amount of heat generated by the preheating heater according to the ambient temperature, and improves maintainability and economy. It's on a higher level.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings. As a light source for an image scanner, a rod-shaped light source is preferable in order to simplify the scanning method, and a rod-shaped fluorescent lamp is usually used. Fluorescent lamps have the disadvantage that the amount of light emitted varies depending on the vapor pressure of the mercury vapor sealed inside, and the amount of light decreases particularly at low temperatures.

The present invention uses a self-regulating heating element heater as a preheating heater to solve the above-mentioned problems, and in this embodiment,
As shown in FIG. 1 and FIG. 2, a self-controlling heating element heater 2 is placed in close contact with or near the side of the fluorescent lamp 1 opposite to the document placement glass 3 to preheat the fluorescent lamp 1. Note that 2a and 2b are power supply electrodes.

FIG. 3 is a diagram showing the characteristics of the self-regulating heating element heater 2. When the ambient temperature is low, the power consumption (heat amount) is large;
Power consumption is low when the ambient temperature is high. Therefore, when the ambient temperature is low and a lot of heat generation from the preheater is required, the power consumption is high, and when the ambient temperature is high and the preheater does not require a lot of heat generation, the power consumption is low. Use as a heater allows temperature control without the need for other control circuits, improving maintainability and economy. Furthermore, in this embodiment, since the self-controlling heating element heater 2 is provided alongside the fluorescent lamp 1 on the opposite side of the document placement glass 3, a decrease in the amount of light irradiated onto the document can be reduced.

〔Effect of the invention〕

According to the present invention, since the temperature can be controlled by the heater itself, there is no need for a temperature control circuit, which improves maintainability.

It has the effect of increasing economic efficiency.

[Brief explanation of the drawing]

Fig. fs1 is a front view of the light source for an image scanner according to the present invention, Fig. 2 is a side view thereof, and Fig. 3 is a diagram showing the characteristics of the self-controlling heating element heater. □l...Fluorescent lamp, 2.
...Self-controlling heating element heater. Continuing from page 1 ■Inventor Tadashi Ito - 1 Higashitaga-cho, Hitachi City
Chome] Inside the factory

Claims (1)

[Claims] 1. A light source device using a fluorescent lamp as a light source, characterized in that the fluorescent lamp is provided with a self-controlling heating element heater.