JPS59128513A - Light signal generating device - Google Patents

Abstract

PURPOSE:To prolong the life of whole device by providing a temperature sensor a little to the wind inlet side from the center of a fluorescent lamp. CONSTITUTION:A micro-light shutter array 1 consisting of a liquid crystal device etc. is illuminated by a fluorescent lamp 2. A luminance sensor 3 feeds back brightness of the fluorescent lamp to a luminance controller 4. A blasting fan 5 can make hot air by a heater 6. A sealing section 9 restricts the extent of air flow and serves as heat insulator. A temperature sensor 7 is placed a little to the wind inlet side from the center of the fluorescent lamp. Accordingly, the wind inlet side can be kept at initially set temperature even when aging of the fluorescent lamp 2 advances and self-heat generation of the lamp 2 increases. The wind outlet side becomes high temperature due to addition of self generated heat. However, the drop of light emitting efficiency of the fluorescent lamp is slower when the temperature is above optimum tube wall temperature than the case when it is below the said temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an optical printer ID generator ilt using a microphone mouth shutter array.

In particular, the present invention relates to improving aging performance in order to obtain a stable optical signal over as long as possible.

As a conventional optical signal generating device using a micro-optical shutter array, one is known that uses a high-speed liquid crystal display to image an optical signal formed by a microphone mouth shutter array using a focusing fiber array. . - An example is Japanese Patent Application Laid-open No. 176719/1983.

The performance required for an optical printer includes high-speed printing performance, double-sided image quality, and long-term reliability. However, if we try to achieve cylinder-speed printing, the time allocated to one microjitter will inevitably become shorter, and the light energy per 111iii will decrease. In addition, even if the area r of the microshutter is reduced to improve the resolution, the MTF% of the optical fiber array is not sufficient, so the amount of light per unit area increases. Energy decreases.

For this reason, the fluorescent lamp, which is the light source, is forced to turn on at high brightness, and the amount of injection that requires a large amount of power is reduced, causing deterioration in aging performance. As a countermeasure for this drawback, conventional methods have been used to control the tube wall temperature of the fluorescent lamp to an optimum temperature using warm air, and a temperature sensor has been installed near the air outlet. Figure 1 Aoi conceptually shows the constituent sounds of a conventional optical signal generator. 1 is a micro light shutter array which is illuminated by 2 fluorescent rungs. 3 is a brightness sensor, which feeds back the brightness of the fluorescent lamp to the brightness controller 4. , 5 is a blower fan that can generate warm air using a white heater. Feedback is sent to the controller. 9 is a sealing part, which has the role of reversing the flow range of lice and moe heat. Sword 1 was chosen because it clearly had the disadvantages shown below.

First, in order to obtain a stable optical signal, the brightness controller 8 controls the brightness of the fluorescent lamp 2. The luminous efficiency of fluorescent rung 2 decreases over time due to its own aging, and as a result, the input power gradually increases. The temperature of the air is determined mainly by the amount of heat generated by the heater 6 and the amount of self-heat generated by the fluorescent lamp 2. The amount of self-heating increases as the power input to the fluorescent lamp 2 increases, so the temperature controller is set to the initially set temperature. In an attempt to maintain the temperature, the chipping of the heater 6 is gradually reduced.
Therefore, as the temperature near the air inlet gradually decreases, the luminous efficiency 91 decreases.

Figure 5 shows that when the tube wall temperature of the fluorescent lamp is varied,
Necessary -24 to maintain constant #1 degree! I'll show you my tail.

As the luminous efficiency decreases, the power input to the fluorescent lamp further decreases, resulting in a vicious cycle, which significantly worsens the aging of the signal generator. An example thereof is shown in FIG. In this example, a vicious cycle began after 500 hours had passed, and the device became unusable after 600 hours.

What are the above drawbacks of this invention? The present invention provides an optical signal generating device a'i that can be used without any problems, and the lifetime of the device as a whole can be approximately doubled compared to the conventional one.

FIG. 2 conceptually shows the entire configuration of the original signal generator according to the present invention. The difference from the conventional example is that the temperature sensor 7 is placed closer to the air inlet than the center of the fluorescent lamp 2. When the temperature sensor is installed in this way, at the beginning when the fluorescent lamp 2 is not aging, the temperature distribution will be almost the same as that of the conventional example. The set temperature is maintained, and the self-heating amount on the air outlet side changes to reach both temperatures. Here, it is clear from the graph of tube wall temperature and required power of the fluorescent lamp in Figure 3 (A, etc., optimum tube wall temperature)
However, the luminous efficiency decreases less when it is heated than when it is cooled. For this reason, a vicious cycle such as /ζ seen in the conventional example is less likely to occur, and the life of the device as a whole can be extended.

Examples will be described below.

The fluorescent lamp 2 is an aperture type fluorescent lamp with a main wavelength of 5 A 5 n rn (MAXt4+i200,000 Cd/
n? .

(tube length: 37 cm, front electrode: 16 mm) Of course, the micro optical shutter array 1 has a glass substrate with at least one common electrode and a glass substrate with several electrodes facing each other, and a liquid crystal display between them. Both $1 for a liquid crystal panel made by completely encapsulating the composition! The liquid crystal composition is made by adding an optically active substance to a nematic liquid crystal whose crossover frequency (hereinafter abbreviated as fQ) at which the dielectric anisotropy becomes zero is 100 KHz or less at room temperature. Further, a signal having a frequency lower than fc (hereinafter abbreviated as f1'1) and a signal having a frequency lower than fc (hereinafter abbreviated as f1) are printed between the common electrode and the signal electrode. 〃The structure is as described above, and compared to the conventional TN type (twisted nematic) liquid crystal device, the shutter operation is 10 times faster and stable at a repetition frequency of 500 Hz. Does the rudder sensor 3 have a load resistance rather than a temperature characteristic that becomes almost zero near room temperature? The attached photodiode has been used for a long time, and the temperature characteristics of the sensor itself have been improved.
The maximum power input to the heater 6 is approximately 7[]W, and fs
Wind! 115 has a pressurized push-in type 7-reed structure tM, and the air volume is 10j/min.It has a temperature sensor and a thermistor, and is located near the air inlet about 2 cm inside from the end of the fluorescent lamp 2. installed, and the set temperature is approximately 40°C. Seal f! A9: It is made of sheet metal and is insulated with 1cm thick styrofoam.

Seven aging tests were conducted for the above implementation u, and the results are shown in FIG. Even after 1000 hours, the above-mentioned vicious cycle did not occur and the product was in a usable state.

The optical generator No. 100 according to the invention constructed as described above, and the Sθ-Te based photosensitive drum system. When installed in a ppc copying machine and subjected to two-component reversal development at a speed of 5 cm/m using a professional printer, it was possible to produce clear and durable prints over a long period of time.

As mentioned above, according to the invention, the fluorescent lamp can be used seven times without having to replace the fluorescent lamp, and it can be used for seven times without maintenance! It became possible to reduce ff1k.

[Brief explanation of drawings]

FIG. 1 shows substantially the entire configuration of a conventional optical signal generator. FIG. 2 shows almost the entire optical signal generating device according to the present invention! 4 results are shown. Figure 3 shows the temperature of the tube wall of the source lamp and the constant brightness! FIG. 4 shows the aging performance of the conventional optical signal generator, as shown in -i+II of the relationship with the power required to maintain the signal. FIG. 5 shows the aging performance r of the optical signal generator according to the invention. 1... Micro light shutter array 2... Fluorescent light rung 5... T41JT sensor 4... Brightness controller 5... Air blower 6... Heater 7... Temperature sensor 8... Temperature controller 9... Seal part and above Applicant: Suwa Kozuko Co., Ltd. Joint Agent Patent Attorney Mogami

Claims (1)

[Claims] In the micro light shutter array and the light source acoustic light signal generating device that supplies light energy to the micro light shutter array, the light source is a fluorescent lamp, and further includes a four-ton sensor, the output of the brightness sensor. In addition to the above, it also includes a device for blowing air to the fluorescent lamp, a heater placed near the device for blowing air, and a temperature sensor. , a temperature controller that changes the electric power input to the heater according to the output of the temperature sensor, and a 7-hole limiter that limits the range of air flow. In the center, near the entrance of the wind! An optical signal generator characterized in that it is installed in J.