JP2003309273A - Light quantity detection means, and illuminator and sensor device having the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light quantity detection means capable of maintaining the high energy utilization efficiency of light incident to the incident plane of a light-transmitting rod, and an illuminator and a sensor device having the light quantity detecting means. <P>SOLUTION: For the light quantity detection means and the illuminator and the sensor device having the light quantity detection means, the light incident to the light-transmitting rod 3 and propagated inside is reflected at a part 3c where a part of an outer side face is roughened near the emission plane of the light transmitting rod 3 and is extracted from the light-transmitting rod 3; and a sensor 4 for monitoring detects the reflected light 1c and light quantity signals corresponding to the change amount of the light 1 incident to the light transmitting rod 3 are outputted. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION A monitor sensor detects a part of light transmitted through a light-transmissive rod and outputs a light amount signal according to a change amount of the light, and a lighting device provided with the light amount detection means. And a sensor device.

[0002]

2. Description of the Related Art An illuminating device having a light amount detecting means for detecting a part of light and outputting a light amount signal according to the amount of change of the light is introduced in Japanese Patent Laid-Open No. 2001-307523. . In this publication, a light source that emits light, a light amount distribution equalizing unit that causes light emitted from the light source to enter from its incident surface, and emits from the emitting surface, and a light amount distribution equalizing unit It is possible to adjust the light guide body which makes a part of the light incident from the incident surface and emits the light from the emitting surface, and the light amount signal voltage obtained by receiving a part of the light emitted from the emitting surface of the light amount distribution uniformizing means. A lighting device is described, which includes a light source control unit that controls light emission of the light source based on a comparison result with a reference voltage. Here, the above-mentioned light source control means receives a part of the light emitted from the emission surface of the light amount distribution equalizing means, and outputs a light amount signal according to the change amount of the light emitted from the light amount distribution equalizing means. Therefore, it has a function as a light amount detecting means.

An illuminating device equipped with such a light amount detecting means will be described with reference to FIG. The light emitted from the lamp 2 is reflected by the reflecting mirror 8, is condensed, and is incident on the incident surface 3 a of the light quantity distribution uniformizing means 3. The light incident on the incident surface 3a propagates inside the light quantity distribution uniformizing means 3, the light path length in the propagation direction is made as long as possible, and the multiple reflections are repeated, whereby the light quantity distribution is made substantially uniform, It is guided to the emission surface 3b. Part of this light is incident surface 5 of light guide 5.
a and the incident surface 10a of the light amount monitoring fiber 10 are incident. The light incident on the incident surface 5a propagates inside the light guide body 5, and the light emitted from the exit surface 5b illuminates an object located at a predetermined external position. On the other hand, the light incident on the incident surface 10 a of the light quantity monitoring fiber 10 propagates inside and is guided to the light receiving element 4. The light receiving element 4 photoelectrically converts the received light amount and outputs a light amount signal voltage to the lamp drive circuit 7. In the lamp drive circuit 7, the light emission of the lamp 2 is controlled so that the light amount signal output from the light receiving element 4 has a predetermined value. Such control is based on the comparison result of the adjustable reference voltage and the light amount signal voltage,
This can be achieved by changing the voltage applied to the lamp 2 with the aim of matching these.

[0004]

However, a light amount detecting means for outputting a light amount signal corresponding to the amount of change of the light by detecting a part of the light described above, and an illuminating device equipped with the light amount detecting means. Still had some problems to solve. That is, firstly, the cross section of the exit surface of the light quantity distribution uniformizing means 3 shown in FIG. 13 has a square shape, and among the lights incident on the entrance surface 3a of the light quantity distribution uniformizing means 3 from the lamp 2, diagonal lines are shown. The light emitted from the above portion becomes leakage light without being guided to the light guide body 5, and there is room for improvement in terms of energy utilization efficiency.

Secondly, since the means for detecting a part of the light is arranged on the emission surface 3b of the light quantity distribution uniformizing means 3,
Due to dirt on the entrance surface 5a and the exit surface 5b of the light guide 5,
Alternatively, it has not been possible to detect a decrease in the amount of light due to a defect in the propagation of light inside the light guide body 5 such as a break in the optical fiber strand.

A first object of the present invention is to provide a light quantity detecting means capable of maintaining a high energy utilization efficiency of the light incident on the incident surface of the light transmissive rod rather than the lamp, and an illuminating device equipped with the light quantity detecting means. It is to provide a sensor device.

A second object of the present invention is to reduce the amount of light due to dirt on the incident surface or the exit surface of the light guide body or due to a defect in the propagation of light inside the light guide body such as a break in the optical fiber strand. As a means for detecting, it is possible to detect a part of the light emitted from the emission surface of the light guide, and output a light amount signal according to the amount of change of the light incident on the light guide. An object of the present invention is to provide a light amount detecting means, and an illumination device and a sensor device including the light amount detecting means.

[0008]

In order to solve such a problem, the invention according to claim 1 takes out a part of the light incident on the light transmissive rod from the light transmissive rod,
A light amount detecting means for detecting a part of the light by a monitor sensor and outputting a light amount signal according to a change amount of the light incident on the light transmissive rod, in the vicinity of an emission surface of the light transmissive rod. Part of the outer surface of the is roughened, the light propagated inside the light transmissive rod is reflected at the roughened portion, and the reflected light is a part of the light It is a light amount detection means.

According to a second aspect of the present invention, a part of the light incident on the lamp that emits light and the light transmissive rod is extracted from the transmissive rod, and a part of the light is detected by the monitor sensor. Then, the light amount detecting means for outputting a light amount signal corresponding to the amount of change of the light incident on the light transmissive rod and the light emitted from the light transmissive rod are made incident and propagate inside the light transmissive rod to obtain an external object. In an illuminating device including a light guide that emits emitted light for illuminating an object, a part of an outer surface of the light transmissive rod near the emission surface is roughened, and the roughened portion In the illumination device, the light propagating inside the light transmissive rod is reflected, and the reflected light is a part of the light.

According to a third aspect of the present invention, the lamp that emits light, the light guide body that allows the light of the lamp to enter, propagates inside the lamp, and emits the emitted light, and the light transmitting rod are provided. A part of the light emitted from the light guide body is extracted from the light transmissive rod, the monitor sensor detects a part of the light, and the change amount of the light incident on the light guide body. A light amount detection means for outputting a light amount signal according to the above, and in an illuminating device for irradiating an object to the outside with light emitted from the light transmissive rod, one of the outer surfaces near the light emission surface of the light transmissive rod. The illuminating device is characterized in that a portion is roughened, and the light propagated inside the light transmissive rod is reflected at the roughened portion, and the reflected light is a part of the light.

According to a fourth aspect of the present invention, a part of the light incident on the lamp that emits light and the light transmissive rod is extracted from the transmissive rod, and a part of the light is detected by a monitor sensor. Then, the light amount detecting means for outputting a light amount signal according to the amount of change of the light incident on the light transmissive rod and the light emitted from the light transmissive rod are made incident and propagate inside the light transmissive rod to detect the outside. A light guide that emits emitted light for illuminating an object, and a detection sensor that detects reflected light or transmitted light from the detection object and outputs a light amount signal according to the detected light. In the provided sensor device, a part of the outer surface in the vicinity of the emission surface of the light transmissive rod is roughened, and the light propagating inside the light transmissive rod is reflected at the roughened portion, The reflected light is part of the light A sensor device according to claim.

In the invention described in claims 1 to 4, the "outer surface near the emission surface" of the light-transmissive rod to be roughened is an outer surface as close as possible to the emission surface of the light-transmissive rod. It refers to the side surface, but the distance from this exit surface to the roughened part is 3 of the total length in the longitudinal direction of the light transmissive rod.
It is preferably 0% or less, and more preferably 20% or less.

As such means for "roughening", it is possible to use physical means such as sandblasting or chemical means such as etching with hydrofluoric acid. Particularly, the means for roughening the surface by sandblasting can easily adjust the position and area of the roughened portion by using a mask. Also, by selecting the size of the particles used for sandblasting, it is possible to easily adjust the surface roughness of the portion to be roughened. The surface roughness of this "roughened" portion is 0.01
The depth of the unevenness is preferably about 1 mm to 1 mm.
The area of the "roughened" portion is preferably determined in consideration of the sensitivity of the monitoring sensor.

Further, the "roughened" portion is provided with a dustproof structure or airtightness for the purpose of preventing a change in scattering effect due to a change in the surface state due to dirt or dew condensation due to dust from the outside. It is preferable to provide the sealing.

In the invention described in claims 2 and 4, the luminous flux emitted from the light transmissive rod and the incident surface of the light guide body are optically coupled with substantially the same size. It is preferable. That is, it is preferable that the dimensional difference between the outer shapes of the light flux and the incident surface and the eccentricity of these arrangements are made as small as possible in consideration of the light amount loss and the economical efficiency. Practically, it is preferable that the eccentricity is 5% or less and the dimensional difference is 5% or less of the diameter. Further, regarding the light flux emitted from the light guide body and the incident surface of the light transmissive rod in the invention according to claim 3 described above,
Similarly, it is preferable that they are optically coupled with substantially the same size.

Here, the above-mentioned "light transmitting rod" is
Is transparent to the wavelength of light emitted by the lamp,
The shape may be a substantially cylindrical shape or a polygonal prism such as a square prism. The "light-transmissive rod" includes an incident surface on which light is incident, a rod body portion that propagates light and repeats internal reflection on the outer surface, and an emission surface on which light is emitted. The outside surface as well as the entrance surface and the exit surface forming the outer shape are preferably mirror-polished except for the "roughened" portion described later. An antireflection film may be applied to the entrance surface and the exit surface as required.

Optical glass, quartz glass, plastics, etc. can be used as the material of the "light-transmitting rod", and it is preferable that the length is longer among the external dimensions. For example, when the shape is a substantially cylindrical shape, Practically, when the diameter is D, the length L is preferably about 3D to 10D,
Diameter D is 1 mm to 20 mm and length L is 10 mm to 1.
00 mm is used.

The above-mentioned "monitor sensor" converts the detected light into a voltage value or a current value and outputs the voltage value or current value, and it is possible to independently configure a photoelectric conversion element such as a photodiode or a phototransistor. is there. In addition, if necessary, the photoelectric conversion element, and optical components such as a lens, a filter, a mirror, and a light transmissive rod that control the light receiving region and the light receiving wavelength, an electronic circuit such as a current-voltage conversion circuit, and the like. It is also possible to combine them. It is possible to provide a plurality of monitor sensors as needed, such as in the case of individually detecting different wavelengths.

The above-mentioned "lamp" is not particularly limited, and an ultrahigh pressure mercury lamp, a mercury xenon lamp, a metal halide lamp, a halogen lamp, a light emitting diode, a laser diode and the like can be used.

The above-mentioned "light guide" is composed of one optical fiber element wire or a large number of bundled optical fiber bundles, as well as one or more lenses, mirrors, prisms, filters and light transmitting rods. Relay lens, condenser lens,
It includes an optical component called a projection lens. If necessary, the optical fiber strands or the optical fiber bundle and any one of the optical components may be combined. The "light guide" includes an incident surface on which light is incident, a light guide main body that propagates light inside and guides the light to an emission surface,
A light emitting surface for emitting light, and is optically coupled to the light transmissive rod.

The above-mentioned "detection sensor" can be provided with a photoelectric conversion element such as a photodiode or a phototransistor independently. Further, this photoelectric conversion element and one optical fiber elemental wire, a plurality of bundled optical fiber bundles, optical components such as one or more lenses, filters, mirrors and light transmitting rods, and electronic circuits such as current-voltage conversion circuits It is also possible to configure by combining and.

The operation of the light amount detecting means according to the present invention will be described with reference to FIG. The light amount detecting means is composed of the light transmitting rod 3 and the monitor sensor 4.
The light 1 incident on the incident surface 3a of the light transmissive rod 3 does not necessarily have a uniform light amount distribution in practical use.
The amount of incident light differs depending on the position (point) of the incident surface 3a, and the amount of change in light over time also differs depending on the position (point) of the incident surface 3a. Therefore, it is difficult to obtain a light amount signal according to the amount of change in light by capturing a part of the light on the incident surface 3a.

The light 1 is incident on the incident surface 3a, and the light 1a introduced therein is approximately 3 to 10 times the diameter or diagonal length of the incident surface 3a in the longitudinal direction. By repeating the reflection on the outer surface having the length of or longer than that, the light 1b has a substantially uniform distribution of the amount of light on the emission surface 3b.

The mechanism by which the distribution of the light quantity is made substantially uniform will be described in more detail with reference to FIGS. 2 and 3. Figure 2
Indicates a cross section at an arbitrary position perpendicular to the longitudinal direction of the light transmissive rod 3, and the reflectance on the outer surface thereof is 10
Assuming 0%, light incident from an arbitrary point 3e on the incident surface 3a propagates through the inside of the incident surface 3a and the exit surface 3e.
It is the schematic diagram which represented with distribution of the light quantity in b on the two-dimensional plane. It should be noted that FIG. 2 does not show a portion 3c where a part of the outer surface according to the present invention is roughened.

In FIG. 3, the light-transmitting rod 3 is shown by a dotted line, but when the light-transmitting rod 3 does not exist, the light incident from an arbitrary point 3e on the light-incident surface 3a is emitted from the light-transmitting rod 3b. When illuminating a surface that is equidistant from, the distribution of the amount of light on an arbitrary straight line of this surface is divided into regions a to e, respectively.

Here, for example, the light illuminating the area a in FIG. 3 is reflected twice on the outer surface of the light transmissive rod 3 in FIG. 2, and the light amount in the area a of FIG. Illuminated with almost the same distribution. Similarly, the light illuminated on the region b is
The outer surface of the light-transmissive rod 3 is reflected once, and the light exit surface 3b is illuminated with a distribution substantially the same as the distribution of the amount of light in the region b in FIG. That is, the distribution of the amount of light on the emission surface 3b of the light transmissive rod 3 shown in FIG. 2 is a superposition of the distributions of the amounts of light from the areas a to e equidistant from the emission surface 3b of FIG. . By superimposing the light amount distributions of the respective regions, the light amount distributions on the emission surface 3b are made substantially uniform.

In the above description, for easy understanding, only the arbitrary point 3e of the incident surface 3a has been described, but the other light 1a incident from the incident surface 3a other than the arbitrary point 3e also has the same effect. Thus, the distribution of the amount of light on the emission surface 3b is made substantially uniform.

A part of this roughly uniformized light 1a also reaches a portion 3c where a part of the outer surface is roughened, which is as close as possible to the emission surface 3b. A part of the light 1a is scattered by the scattering effect of the rough surface, is extracted from the outer surface of the light transmissive rod 3 which faces, and becomes the light 1c which is directed to the monitor sensor 4. The monitor sensor 4 detects the light 1c and photoelectrically converts the light 1c, and then outputs a light amount signal according to the amount of change in the light incident on the light transmissive rod 3. on the other hand,
The light amount of the light 1b is emitted from the emission surface 3b while maintaining a high transmission efficiency of about 90% or more of the light amount of the light 1 incident from the incident surface 3a.

[0029]

BEST MODE FOR CARRYING OUT THE INVENTION The light amount detecting means described in claim 1 will be described as a first embodiment with reference to FIG. The light-transmitting rod 3 is a substantially cylindrical quartz glass rod having a diameter of 7 mm and a length of 50 mm, and the monitor sensor 4 is constituted by a photodiode 4a and a current-voltage conversion circuit 4b.

Of the outer side surface 3d, the light transmissive rod 3 is about 3 mm closer to the incident surface 3a by about 4 mm from the emitting surface 3b.
A portion 3c of φmm is roughened by sandblasting (count 200). In the monitor sensor 4, the center of the light receiving surface 4c of the photoelectric conversion element 4a is the light transmissive rod 3
Of the outer side surface of the outer surface of the roughened portion 3c is arranged to face the center of the roughened portion 3c on a substantially straight line, and the roughened portion 3c is reached. It is fixed so as to detect the light scattered and extracted from the opposing outer surface 3d.

Further, the outer surface 3d of the light-transmitting rod 3 is formed.
Has a dustproof structure surrounded by a metal tube 9 made of stainless steel. The light transmissive rod 3 and the metal tube 9 are fixed by contacting only the regions of 1 mm width at both ends of the outer surface 3d and the inner surface 9a. Outside surface 3d other than this area
The inner surface 9a and the inner surface 9a are not in contact with each other, and the gap is kept hollow. Also, the outer surface 3 of the light transmissive rod 3
A light extraction hole 9b having a size of about 4φ mm is formed in the metal tube 9 surrounding a region of the photoelectric conversion element 4a facing the light receiving surface 4c of d.

A lighting device according to claim 2 will be described as a second embodiment with reference to FIG. This lighting device
It is an ultraviolet illuminator used for exposing a photosensitive material and curing an ultraviolet curable resin. In addition, this lighting device is
In addition to the light amount detecting means used in the above embodiment, the lamp 2, the reflecting mirror 8, the mechanical diaphragm 6, the optical fiber light guide 5, and the lamp power supply / control circuit 7 are included.

As the lamp 2, a short arc type 200 W ultra high pressure mercury lamp which mainly emits ultraviolet rays is used. The reflecting mirror 8 reflects the light 1 emitted from the lamp 2 and guides the light 1 to the incident surface 3 a of the light transmissive rod 3.
The mechanical diaphragm 6 blocks a part of the light 1 reflected by the reflecting mirror 8 and controls the amount of light transmitted. The mechanical diaphragm 6 is composed of a circular metal plate 6a and a motor 6b. The surface of this metal plate 6a is fan-shaped from the center thereof.
The light transmittance is changed in each section by changing the size and density of the holes to be formed in each section. By controlling the rotation of the metal plate 6a by the motor 6b, the amount of light incident on the incident surface 3a of the light transmissive rod 3 is continuously controlled.

The optical fiber light guide 5 has a diameter of 20.
Approximately 1000 optical fiber wires made of quartz glass having a diameter of 0 φμm were bundled, and both ends were aligned and adhered to each other.
b has a diameter of about 7 mm. The entrance surface 5a and the exit surface 3 of the light-transmissive rod 3 which constitutes the light amount detecting means.
The luminous flux emitted from b is approximately the same size as the diameter of 7 mm, and is optically coupled so that the eccentricity is within 1.5% and the gap between both is 0.1 mm or less.

The lamp power source / control circuit 7 is a power source for supplying electric power to the lamp 2 and the motor 6b, and serves as a means for setting the amount of light emitted from the emission surface 5b of the optical fiber light guide 5. It has a voltage setting means. The reference voltage setting means is means for presetting a reference value to be compared with the light amount signal output from the monitor sensor 4. The lamp power source / control circuit 7 is also provided with a calculating means for comparing the light amount signal output from the monitor sensor 4 with the reference value, and from the emitting surface of the optical fiber light guide 5 according to the calculation result. It is provided with a means for controlling the mechanical diaphragm 6 so that the emitted light amount becomes a light amount based on the reference value.

Next, the operation of this ultraviolet lighting device will be described. Electric power is supplied to the lamp 2 from the lamp power source / control circuit 7, and the light 1 emitted from the lamp 2 is reflected by the reflecting mirror 8 and the incident surface 3 a of the light transmissive rod 3.
Is incident on. Light 1 introduced into the light-transmitting rod 3
Based on the action of the light amount detecting means described above, 90% or more of the light 1b reaches the emission surface 3b, and a part of the light 1c is emitted.
Is received by the monitor sensor 4. The monitor sensor 4 photoelectrically converts this light 1c by a photodiode, converts it into a voltage by a current-voltage conversion circuit, and then outputs a light amount signal corresponding to the amount of change of the light incident on the light transmissive rod 3,
Output to the lamp power supply / control circuit 7. The lamp power supply / control circuit 7 compares the light amount signal with the reference value and controls the mechanical diaphragm 6 so that they are equal to each other.

Here, the high energy utilization efficiency of the light 1 incident on the inside of the light transmissive rod 3 from the lamp 2 was confirmed by experiments as follows. Light-transmissive rod 3
The ultraviolet intensity on the incident surface 3a and the outgoing surface 3b of was measured using an ultraviolet intensity meter. The light intensity of the light 1 incident on the incident surface 3a was 1,750 mW, and the light intensity of the light 1b emitted from the emitting surface 3b was 1,600 mW. It was confirmed that, out of the light 1a incident on the incident surface 3a of the light transmissive rod 3, 90% or more of the light 1b is emitted from the emission surface 3b.

Further, the light 1b emitted from the emission surface 3b of the light-transmissive rod 3 is incident from the incident surface 5a of the optical fiber light guide 5 shown in FIG. To be done. The light intensity incident on this incident surface 5a is 1,200 mW. This is JP 2001-30
The energy utilization efficiency of the light 1 incident on the incident surface 3a of the light transmissive rod 3 according to the conventional technique described in Japanese Patent No. 7523 is about 28% higher. On the other hand, it was confirmed by experiments that the light amount loss of the light 1 due to the monitor sensor 4 provided with the light amount detecting means for detecting the light 1c is about 1%, which is very small.

Next, the relationship between the ultraviolet intensity on the emission surface 5b of the optical fiber light guide 5 and the voltage output from the monitor sensor 4 will be described with reference to FIGS. First, the lamp 2 shown in FIG. 5 is turned on, the mechanical diaphragm 6 is controlled by the lamp power source / control circuit 7, and the light incident on the incident surface 3 a of the light transmissive rod 3 is intentionally set to 1
It was changed to stage 00.

Here, the ultraviolet intensity on the emission surface 5b of the optical fiber light guide 5 and the voltage output by photoelectrically converting the light 1c received by the monitor sensor 4 by the photodiode were measured. Figure 6
Is the exit surface 5b of the optical fiber light guide 5 described above.
3 shows the relationship between the ultraviolet intensity and the output voltage of the monitor sensor 4 in FIG. According to this, clear linearity is seen in both, and by detecting a part of the light, it is sufficient as a means for outputting a light amount signal according to the change amount of the light incident on the light transmissive rod 3. It has shown that it has an effect.

Therefore, the optical fiber light guide 5
The light emitted from the light emitting surface 5b is the reference value of the reference light amount setting means based on the desired light amount and the change amount of the light that is output from the monitor sensor 4 and is incident on the light transmissive rod 3. By comparing the light amount signal according to the above and controlling the mechanical diaphragm 6 so that they become equal, the light amount becomes stable.

Next, the lighting device according to the third aspect is provided with a third
An embodiment will be described with reference to FIG. In this embodiment, the light quantity detecting means shown in FIG. 4 is used in the first and second embodiments, except that the light quantity detecting means is arranged on the exit surface 5b side of the optical fiber light guide 5. The configuration is used.

Power is supplied to the lamp 2 from the lamp power source / control circuit 7, and the light emitted from the lamp 2 is reflected by the reflecting mirror 8 and is incident on the incident surface 5a of the optical fiber light guide 5. It propagates inside and is emitted from the emission surface 5b. Further, this light is incident on the incident surface 3a of the light transmissive rod 3, part of the light is received by the monitor sensor 4 and photoelectrically converted based on the action of the light amount detecting means described above, and then this light is converted. The voltage is output as a light amount signal corresponding to the amount of change of the light incident on the transparent rod 3. on the other hand,
90% or more of the amount of light incident on the entrance surface 3a reaches the exit surface 3b of the light transmissive rod 3, and this light is emitted from the exit surface 3a.
The light is emitted from b.

Here, it was confirmed by experiments that this ultraviolet illuminator can detect a decrease in the amount of light when some trouble occurs in the propagation of light inside the optical fiber light guide 5. The same lamp 2 is turned on, and five optical fiber light guides 5 with different transmittances are prepared in advance.
These were exchanged and used, light was made incident on the incident surface 5a of each optical fiber light guide 5, and the amount of light emitted from the emitting surface 3b of the light transmissive rod 3 was measured.

FIG. 8 shows the relationship between the intensity of each ultraviolet ray on the emission surface 3b and the voltage output from the monitoring sensor 4 described above. According to this, a distribution based on a certain linearity is seen in both, and by detecting a part of the light, a light amount signal corresponding to the change amount of the light incident on the light transmissive rod 3 is output. It shows that it has an effect as a means. Therefore, it is possible to detect a decrease in the amount of light at the emitting surface 5b due to contamination of the incident surface 5a or the emitting surface 5b of the optical fiber light guide 5 or an abnormality in the internal transmittance such as a fiber break, and to determine the amount of light according to the amount of change in light. It is possible to output a signal.

The light amount detecting means according to the present invention has a very simple structure in which the monitor sensor 4 directly receives the light extracted from the outer surface of the light transmitting rod 3. For this reason, it is possible to easily reduce the size as compared with the light amount detecting means which is conventionally used in the general illumination device and has a configuration requiring a monitor light guide.

In the illumination devices of the second and third embodiments described above, the mechanical diaphragm 6 is used as a means for controlling the light 1 incident on the incident surface 3a of the light transmissive rod 3. As such a control means for the light 1, there is another means for controlling the power supplied to the lamp 2 from the lamp power supply / control circuit 7 and controlling the light 1 emitted from the lamp 2.

Next, the sensor device according to claim 4 is
A fourth embodiment will be described with reference to FIG. This sensor device is a reflectance measuring device that measures the reflectance of the detection target 13. The lamp 2 mainly uses a light-emitting diode that emits red light, and the optical fiber light guide 5 is composed of a multi-component glass optical fiber element wire having a diameter of 50 φm.
00 pieces are bundled, both ends thereof are aligned and adhered, and the entrance surface 5a and the exit surface 5b are configured to have a diameter of about 2φ mm. The incident surface 5a and the light flux emitted from the emission surface 3b of the light transmissive rod 3 are both substantially the same size as the diameter 2φ mm, the eccentricity is about 1%, and the gap between them is 0.5 mm or less. Are optically coupled so that

The light amount detecting means uses a multi-component glass rod having a diameter of 2φ mm and a length of 20 mm as the light transmitting rod 3, and among the outer side surfaces of the light transmitting rod 3,
The configuration used in the first embodiment is used, except that a portion 3c of about 1 mm in the position closer to the entrance surface 3a by about 4 mm from the exit surface 3b is roughened. The detection sensor is composed of a detection optical fiber light guide 14, a detection photoelectric conversion circuit 15 having a photoelectric conversion element and a current-voltage conversion circuit. In this embodiment, a photodiode is used as the photoelectric conversion element.

In this sensor device, in addition to the above,
A condenser lens 11 that condenses the light emitted from the lamp 2 and guides it to the light transmissive rod 3, and an arithmetic circuit 16 that compares the light amount signals output from the monitor sensor 4 and the detection sensor are provided. Has been.

The light emitted from the light emitting diode 2 is condensed by the condenser lens 11, enters from the incident surface 3b of the light transmissive rod 3, and a part of the light is detected based on the action of the light amount detecting means. The monitor sensor 4 receives this light, photoelectrically converts it, and then transmits the light-transmitting rod 3
The light amount signal corresponding to the change amount of the light incident on the arithmetic circuit 1
Output to 6. On the other hand, if the amount of light incident on the incident surface 3a is 9
0% or more is emitted from the emission surface 3b of the light transmissive rod 3 and is incident on the incidence surface 5a of the optical fiber light guide 5. This light propagates inside the optical fiber light guide 5, and is emitted from the emission surface 5b to illuminate the detection target 13.

Reflected light is reflected from the object to be detected 13 based on its reflectance, is made incident from the incident surface 14a of the light guide 14 for detection, propagates inside, and is emitted from this exit surface 14.
It is emitted from b. A photodiode provided in the detection photoelectric conversion circuit 15 receives a part of the reflected light emitted from the emission surface 14b, performs photoelectric conversion, and then is voltage-converted by the current-voltage conversion circuit to detect the object to be detected. A light amount signal corresponding to the reflectance of 13 is output to the arithmetic circuit 16.

In this reflectance measuring apparatus, a reference object whose reflectance is clear, such as a standard white plate, is prepared, and the reflectance (R ₀ ) and the voltage (E) output from the photoelectric conversion circuit 15 for detection are prepared. _d0 ) and these values are calculated by the arithmetic circuit 1
It is entered in 6 in advance. The voltage output from the detection photoelectric conversion circuit 15 obtained by measuring the detection target 13 (E
_d1 ) and the calculation circuit 16 performs the calculation shown in the following Expression 1 to obtain and output the reflectance (R ₁ ) of the detection target 13. R ₀ : reflectance of reference object R ₁ : reflectance of detection object E _d0 : output voltage of photoelectric conversion circuit 15 for detection of reference object E _d1 : output voltage of photoelectric conversion circuit 15 for detection of detection object E _m0 : Output voltage of the monitor sensor 4 when detecting the reference object E _m1 : Output voltage of the monitor sensor 4 when detecting the detection object

However, in the light emitting diode 2, the amount of light emitted changes due to the change in luminous efficiency over time, and the amount of light illuminating the detection target 13 also changes. This variation also varies the output voltage (E _d1 ) from the detection photoelectric conversion circuit 15 according to the reflectance (R ₁ ) of the detection target 13 and detects the same detection target even when the same detection target is measured. Photoelectric conversion circuit 15
The output voltage was different and it was difficult to measure the reflectance accurately.

Even in such a case, the reflectance (R ₀ ) of the reference object and the output voltage (E
3 values of _d0 ) and the output voltage (E _m0 ) from the monitor sensor 4 are input to the arithmetic circuit 16 in advance,
The output voltage (E _d1 ) from the detection photoelectric conversion circuit 15 obtained by measuring the detection target 13 and the monitor sensor 4
And more of the output voltage (E _m1), that is calculated by the equation 2, to correct the output voltage of the detection photoelectric conversion circuit 15 which varies with change in the amount of light that illuminates the object to be detected 13 (E _m1) Therefore, it is possible to accurately obtain the reflectance (R ₁ ) of the detection target 13. The output form of the reflectance (R ₁ ) from the arithmetic circuit 16 can be an analog value output such as current or voltage, or a digital output value.

Although the sensor device of this embodiment is a reflectance measuring device, a transmittance measuring device, a color identification sensor device,
It can also be used in optical film thickness measuring devices, refractometers, densitometers, gloss meters, and the like.

Further, in this embodiment, the illuminating optical fiber light guide 5 and the detecting optical fiber light guide 14 constituting the detecting sensor are individually provided, but as shown in FIG. It is also possible to configure the detection target side of the two optical fiber light guides as an integrated body. In this case, it is possible to illuminate light on a detection target having a minute size, receive light reflected from the detection target, and perform measurement.

Further, as shown in FIG. 11, it is possible to allow the detection photoelectric conversion circuit 15 to directly receive the transmitted light from the detection object 13 without providing the detection optical fiber light guide 14 in the detection sensor. . In this case, it becomes possible to measure the transmittance of the transmission object such as a liquid or the semi-transmission object as the detection object 13.

[0059]

As described above in detail, according to the present invention, firstly, there is provided a light quantity detecting means capable of maintaining a high energy utilization efficiency of the light incident on the incident surface of the light transmissive rod than the lamp, and a light quantity detecting means. It is possible to provide a lighting device and a sensor device provided with this. Secondly, when there is a decrease in the amount of light due to dirt on the entrance surface or the exit surface of the light guide, or when there is some problem in the propagation of light inside the light guide due to a break in the optical fiber strand, etc. As a means for detecting the decrease of the light, a part of the light emitted from the emission surface of the light guide is detected as necessary, and a light amount signal corresponding to the change amount of the light incident on the light guide is output. It is possible to provide a light amount detection means capable of performing the above, and an illumination device and a sensor device including the same.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a light amount detecting means of the invention according to claim 1.

FIG. 2 is an aspect of light propagating inside a light transmissive rod,
It is a schematic diagram which shows distribution of the light quantity in an emission surface.

FIG. 3 is a schematic diagram showing an optical path in the absence of a light transmissive rod and a distribution of the amount of light on a surface equidistant from the emission surface.

FIG. 4 is a schematic view showing a light amount detecting means showing an embodiment of the invention described in claim 1.

FIG. 5 is a schematic diagram of an illumination device showing an embodiment of the invention described in claim 2.

FIG. 6 is a chart showing the correlation between the ultraviolet intensity of the emission surface of the optical fiber light guide and the output voltage from the monitor sensor in the illumination device according to the second aspect of the invention.

FIG. 7 is a schematic diagram of an illumination device showing an embodiment of the invention according to claim 3.

FIG. 8 is a chart showing the correlation between the ultraviolet intensity of the emission surface of the light transmissive rod and the output voltage from the monitor sensor in the lighting device of the third aspect of the invention.

FIG. 9 is a schematic view of a sensor device showing an embodiment of the invention described in claim 4.

FIG. 10 is a schematic view showing an embodiment of a sensor device.

FIG. 11 is a schematic view showing an embodiment of a sensor device.

FIG. 12 is a schematic view showing a conventional lighting device.

FIG. 13 is a cross-sectional view showing a mode of connection between a conventional light amount distribution uniformizing means and a monitor light guide.

[Explanation of symbols]

1,1a, 1b, 1c light 2 lamps 3 Light-transmissive rod 3c roughened outer surface 4 Monitor sensor 5 Light guide, optical fiber light guide 13 Detection target 14 Optical fiber light guide for detection 15 Photoelectric conversion circuit for detection

Claims (4)

[Claims] 1. A part of the light incident on the light transmissive rod is extracted from the light transmissive rod, a part of the light is detected by a monitor sensor, and is incident on the light transmissive rod. In the light amount detecting means for outputting a light amount signal according to the amount of change in light, a part of the outer side surface in the vicinity of the emitting surface of the light transmitting rod is roughened, and the light transmissive portion is roughened. A light amount detecting means for reflecting the light propagating inside the rod, the reflected light being a part of the light. 2. A lamp that emits light, and a part of the light that is incident on the light transmissive rod is extracted from the transmissive rod, and a part of the light is detected by a monitor sensor, Light amount detection means for outputting a light amount signal according to the amount of change of light incident on the transparent rod, and light emitted from the light transparent rod is made incident and propagates inside this to illuminate an external object. In a lighting device provided with a light guide that emits emitted light for, a part of the outer surface of the light transmissive rod in the vicinity of the emitting surface is roughened, and the light is emitted at the roughened portion. An illuminating device that reflects light propagating inside a transparent rod, and the reflected light is a part of the light. 3. A lamp that emits light, a light guide that allows the light of the lamp to enter, propagates inside the lamp, and emits emitted light, and a light transmissive rod that emits the light emitted from the light guide. A part of the incident light is taken out from the light transmissive rod, the monitor sensor detects a part of the light, and outputs a light amount signal according to the change amount of the light incident on the light guide. In the illuminating device, which comprises a light amount detecting means for illuminating an external object, the light emitted from the light transmissive rod is roughened at a part of the outer surface of the light transmissive rod in the vicinity of the light emitting surface, An illuminating device characterized in that the light propagated inside the light-transmitting rod is reflected at the roughened portion, and the reflected light is a part of the light. 4. A lamp for emitting light and a light transmissive rod, part of the light incident on the light is extracted from the transmissive rod, and a part of the light is detected by a monitor sensor,
A light amount detection unit that outputs a light amount signal according to the amount of change of the light incident on the light transmissive rod, and the light emitted from the light transmissive rod is incident, propagates inside the light transmissive rod, and is externally detected. A light guide that emits emitted light for illuminating an object, and a detection sensor that detects reflected light or transmitted light from the detection target and outputs a light amount signal according to the detected light In the sensor device, a part of the outer surface in the vicinity of the emission surface of the light transmissive rod is roughened, and the light propagated inside the light transmissive rod is reflected at the roughened portion, and this reflection A sensor device, wherein light is a part of the light.