JP3246802B2 - Image reading device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image reading apparatus comprising an image reading apparatus using a fluorescent tube and a transparent original unit mounted on the image reading apparatus using the fluorescent tube.

[0002]

2. Description of the Related Art When a fluorescent tube is used as a light source for an image reading apparatus main body and a transparent original unit, it takes several minutes until the light quantity becomes stable, and about 10 minutes in a low temperature environment. Since it is necessary to be able to read any of them, the light sources of both the image reading apparatus main body and the transparent original unit are always kept warm.

[0003]

Therefore, in the conventional apparatus, a heater is provided so as to always warm the light source. However, there is a disadvantage that the provision of the heater increases the cost. The present invention provides a self-contained fluorescent tube for an image reading apparatus.
Insulation and self-heating of the transparent original unit can be controlled and controlled.
An object of the present invention is to provide an image reading apparatus capable of simplifying a road .

[0004]

SUMMARY OF THE INVENTION The object of the present invention is to provide an image reading apparatus body using a fluorescent tube as a light source, a transparent original unit mounted on the image reading apparatus body also using a fluorescent tube as a light source. An image reading apparatus comprising:
The light intensity of the light source of the
Turn on the light source of the image reading device, and then
The amount of light detected by the
Time until the same time as the measured time
Only by turning on the fluorescent tube of the transparent original unit
The self-heating of the fluorescent tube of the image reading device body and the transparency
This is achieved by the first means for performing the self-heating of the over-document unit . Further, the first means is achieved by a second means in which the light amount detection sensor is provided only in the image reading apparatus main body. Further, in the first and second means, it is achieved by a third means in which the fluorescent tube of the image reading apparatus main body and the fluorescent tube of the transparent original unit are turned on alternately.

[0005]

In the first means, the firefly of the image reading apparatus main body is provided.
By detecting only the light intensity of the light tube with the light intensity detection sensor
Self-heating of the fluorescent tube of the image reading device and the transmission original
In the second means capable of keeping the unit self-heating , the above operation is performed by a light amount detection sensor provided only in the image forming apparatus main body . In the third means, the power supply load is reduced by not lighting the two fluorescent tubes at the same time.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic diagram of an image reading apparatus according to an embodiment, and FIG.
3A and 3B are a flowchart of the control of turning on / off the fluorescent tube with respect to the time of the image reading apparatus main body 1 and the transmission original unit 10, and a timing chart of the control of turning on the fluorescent tube.

In FIG. 1, reference numeral 1 denotes an image reading apparatus main body, which includes a fluorescent tube 2, a first mirror 3, a second mirror 4, a third mirror 5, an imaging lens 6, a CCD (light receiving element) 7, and a fluorescent light. A light amount detection sensor 8 is provided near the tube 2 and detects the light amount of the fluorescent tube 2. Reference numeral 10 denotes a transparent document unit placed on the upper portion of the image reading device main body 1, and includes a fluorescent tube 11, similarly to the image reading device main body 1.

Next, control of turning on / off the fluorescent tube with respect to the time of the image reading apparatus main body 1 and the transmission original unit 10 is shown in FIG.
This will be described with reference to the flowcharts of FIGS.
Here, parameters are defined. Vth: a value below which the fluorescent tube cannot be stable. epsilon; determination value _{(V n -V n-1)} / V n is deemed fluorescent tubes not more than this value is stable. V _n ; _n after lighting the fluorescent tube 2 of the image reading apparatus main body 1
Light quantity sampled the second time. Δt: sampling interval. C: counter (+1 is added every time Δt elapses after the fluorescent tube 2 of the image reading apparatus main body 1 is turned on).

In FIG. 2, first, the fluorescent tube 2 of the image reading apparatus main body 1 is turned on (S1), and C is cleared (= 0) (S1).
2). After Δt has elapsed (Y in S3), C is incremented by 1 (S
4), to detect the V ₁ (S5), stores (S6). Further, after elapse of Δt (Y in S7), C is incremented by 1 (S8),
Detecting the V ₂ (S9), (N at S10) if it is V ₂ ≦ Vth, to clear the V ₁ to save the _{V 2 (S11), V n} > Vt
It repeats until it becomes h (Y in S10). Once you become a _{V n> Vth, (V n} -V n-1) / V n to the _{calculation, (V n -V n-1} )
If / V _n > ε (N in S12), then (V _n −V
_n−1 ) / V _n ≦ ε (Y in S12).
When _{(V n -V n-1)} / V n ≦ ε and turned, turns off the fluorescent tube 2 of the image reading apparatus main body 1 (S13), and then turns on the fluorescent tube 11 of the transparent original unit 10 (S14). After elapse of Δt (Y in S15), C is decremented by 1 (S16), and C = 0
(Y in S17). When C = 0, the fluorescent tube 11 of the transparent original unit 10 is turned off (S1).
8) The fluorescent tube 2 of the image reading apparatus main body 1 is turned on. Therefore, the fluorescent tube 11 of the transmission original unit 10 is the same as the time during which the fluorescent tube 2 of the image reading apparatus main body 1 is turned on.
Is turned on, the image reading apparatus main body 1
If the fluorescent tube 2 is warmed up, the fluorescent tube 11 of the transmission original unit 10 is also warmed up.

By repeatedly performing this process, the fluorescent light tubes 2, 1 of both the image reading device main body 1 and the transparent original unit 10 are detected by the light amount detection sensor 8 of only the image reading device main body 1.
3 can be realized, and as shown in FIG. 3, since both are not turned on at the same time, no load is applied to the power supply.

[0011]

According to the first aspect of the present invention, an image is read.
The light intensity sensor detects only the light intensity of the fluorescent tube of the main unit.
The self-heating of the fluorescent tube of the image reading device
The self-heating of the transparent original unit can be performed,
Simplification can be achieved. According to the second aspect of the present invention, it is not necessary to provide a light amount detection sensor in the transparent original unit, so that cost can be reduced. 請 Motomeko
According to the invention described in the third aspect, since the fluorescent tube of the image reading apparatus main body and the fluorescent tube of the transmission original unit are not turned on at the same time, it is not necessary to load the power supply.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of an image reading apparatus according to an embodiment of the present invention.

FIG. 2 is a flowchart of control of turning on / off a fluorescent tube with respect to time of an image reading apparatus main body 1 and a transparent original unit 10;

FIG. 3 is a timing chart of fluorescent tube lighting control.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Image reading apparatus main body 2 Fluorescent tube 8 Light quantity detection sensor 10 Transmission original unit 11 Fluorescent tube

Continuation of front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G03B 27/54 G03G 15/00 H04N 1/04

Claims (3)

(57) [Claims] An image reading apparatus main body using a fluorescent tube as claimed in claim 1 light source, the same image reading apparatus comprising a transparent original unit placed on the image reading apparatus on the body using a fluorescent tube as a light source, the image reading apparatus main body The light intensity of the light source is
After detecting and turning on the light source of the image reading apparatus,
Consider that the amount of light detected by the amount detection sensor is stable
Time until the amount of light reaches
Turn on the fluorescent tube of the transparent original unit for the same time as
By doing so, the fluorescent tube of the image reading apparatus main body can be self-maintained.
An image reading apparatus for performing self-heating of the transparent original unit and a temperature of the transparent original unit . 2. The image reading apparatus according to claim 1, wherein
An image reading device, wherein the light amount detection sensor is provided only in the image reading device main body. 3. The image reading according to claim 1, wherein the image is read.
The image reading apparatus according to claim 1, wherein the fluorescent tube of the image reading device main body and the fluorescent tube of the transparent original unit are alternately turned on.