JP2010245483A - Light output device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To emit each of a plurality of laser beams of three wavelengths or more without synthesis onto the same optical axis by using light transmitting/reflecting mirrors without using an adjustment mechanism such as light path adjustment and alignment of polarization planes. <P>SOLUTION: An light output device is such structured that a laser beam with a specific wavelength is selectively extracted among laser beams emitted from a plurality of semiconductor lasers 11, 12 and 13 by light transmitting/reflecting mirrors 14 and 15, a laser beam with the specific wavelength extracted through the light transmitting/reflecting mirrors 14 and 15 is focused by focusing lenses 16 and 17, the laser beam is led onto the same optical axis, and a plurality of laser beams with different wavelengths are serially output onto the same optical axis. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an optical output device used for measuring properties of an inspection object by irradiating the inspection object with laser beams having a plurality of specific wavelengths.

  Conventionally, various optical output devices that collect and output laser beams having different wavelengths on the same optical axis have been proposed (see, for example, Patent Document 1). This light output device records and reads information while scanning a combined light of a laser beam on a recording medium, and has a configuration as shown in FIG.

  This optical output device includes a first semiconductor laser 21 and a second semiconductor laser 22 that oscillate a laser beam, and a wave plate that is disposed on the oscillation side of these semiconductor lasers 21 and 22 and changes the polarization plane of the laser beam. 23, 24, a polarizing beam splitter 25 for combining the laser beams that have passed through the wave plates 23, 24, and a scanning optical system 26 for scanning the laser beam combined by the polarizing beam splitter 25. Is configured.

  In this laser beam recording apparatus, the semiconductor lasers 21 and 22 and the wave plates 23 and 24 are arranged so that the long axes of the cross-sectional shapes of the laser beams intersect at substantially the center and the laser beams are synthesized. It is. Reference numerals 27 and 28 denote collimator lenses that convert the laser beams oscillated by the semiconductor lasers 21 and 22 into parallel beam bundles, reference numeral 29 denotes a light converging lens, and reference numeral 30 denotes a recording medium on which recording is performed by receiving the laser beams.

  According to this light output device, the laser beam oscillated from each of the semiconductor lasers 21 and 22 is converted to P-polarized light or S-polarized light and enters the polarizing light splitter 25. Further, the polarization light splitter 25 combines the long axes of the cross-sectional shapes of the respective laser beams at the central portion. The light energy of the superposed part of the synthesized laser beam becomes high intensity. The superimposed combined light is deflected by an optical deflector 26 that is a scanning optical system, and then converged into a light spot by a focusing lens 29 and is incident on a recording medium 30.

Japanese Patent Laid-Open No. 1-146748

  However, in the conventional light output device, the main purpose is to obtain high-intensity light energy by synthesizing the laser beams, and two semiconductor lasers oscillate in the synthesizable laser beam. There are only two wavelengths, and a laser beam having three or more wavelengths cannot be synthesized. Furthermore, in order to adjust the optical path including the condensing lens and align the polarized light surface, the wave plates 23 and 24 must be arranged on the optical axis, which complicates the configuration and makes the entire light output system large. Electricity and cost will increase.

  The present invention has been made paying attention to such a conventional inconvenience, and by using a light transmission / reflection mirror without using an adjustment mechanism such as adjustment of an optical path or alignment of a polarized light surface, three or more different wavelengths can be obtained. It is an object of the present invention to obtain a light output device that allows a plurality of laser beams to be emitted in a time-sharing manner on the same optical axis instead of combining them.

  In order to achieve the above object, an optical output device according to the present invention includes a plurality of semiconductor lasers each emitting a laser beam having a specific wavelength, and a laser beam having a specific wavelength emitted from these semiconductor lasers. A plurality of light transmission / reflection mirrors that are separated from light and taken out on one optical axis are aligned with the focal position of laser light of a specific wavelength extracted through each of these light transmission / reflection mirrors, And a plurality of laser beams having different wavelengths on the optical axis are serially output.

  With this configuration, each light transmitting / reflecting mirror serially outputs only a plurality of laser beams having different wavelengths on the same optical axis, and irradiates the inspection target with laser beams having different wavelengths that are serially output. Measurement data corresponding to each wavelength can be obtained from this inspection object. Therefore, by analyzing the measurement data, it is possible to determine the property of the inspection target.

  In addition, the light output device according to the present invention is characterized by having a configuration in which two light transmitting / reflecting mirror members each having a rectangular plate shape are assembled in a cross-integral manner or integrally formed at a central portion.

  With this configuration, only one light transmitting / reflecting mirror 18 needs to be prepared and installed in the optical system, so that the assembly work of the light output device can be made more efficient, the entire device can be made smaller, and the occupied space can be reduced. And cost reduction can be realized.

  According to the present invention, a plurality of laser beams having three or more wavelengths can be obtained with a simple configuration using a light transmission / reflection mirror and a focusing lens without using an adjustment mechanism such as adjustment of an optical path or alignment of a polarized light surface. Data can be serially output on the same optical axis, and data such as the properties of the inspection object can be collected by irradiating the inspection object with laser beams having different wavelengths.

It is a schematic block diagram which shows the light output device by embodiment of this invention. It is a schematic block diagram which shows the light output device by other embodiment of this invention. It is a schematic block diagram which shows the light output device by other embodiment of this invention. It is a schematic block diagram which shows the principal part of the light output device by another embodiment in this invention. It is a schematic block diagram which shows the conventional beam output apparatus.

Hereinafter, embodiments of a light output device according to the present invention will be described in detail with reference to the drawings.
Here, FIG. 1 is a schematic configuration diagram illustrating a light output device according to the present embodiment, FIG. 2 is a schematic configuration diagram illustrating a light output device according to another embodiment, and FIG. 3 is a light output according to still another embodiment. It is a schematic block diagram which shows an apparatus.

  The light output device according to the present embodiment includes a plurality of semiconductor lasers, a light transmission / reflection mirror, and a focusing lens or a collimating lens. Note that there are cases where the focusing lens or the collimating lens is not needed because the light spread is small due to the radiation angle of the laser light when the optical path length is short. Specifically, the plurality of semiconductor lasers include a first semiconductor laser 11, a second semiconductor laser 12, and a third semiconductor laser 13. The plurality of light transmission / reflection mirrors include a first light transmission / reflection mirror 14 and a second light transmission / reflection mirror 15. Further, the plurality of focusing lenses include a first focusing lens 16 (focal position f1) and a second focusing lens 17 (focal position f2).

  Each of the first to third semiconductor lasers 11 to 13 generates laser light in a predetermined wavelength region (frequency region) by exciting the PN junction of the semiconductor by flowing a current. These semiconductor lasers 11 to 13 are small and light and have a wide range of oscillation wavelengths from blue to infrared, but are less directional than other lasers and easily diffuse.

The first and second light transmitting / reflecting mirrors 14 and 15 are provided with a laser light reflecting surface by a metal vapor deposition film on one surface of transparent glass, and the other surface is a laser light transmitting surface. These first and second light transmitting / reflecting mirrors 14 and 15 have a wavelength filter function of transmitting or reflecting a laser beam having a specific wavelength suitable for irradiation of an inspection object and leading it to a predetermined optical axis. Therefore, the reflecting surface functions to select or transmit laser light having a specific wavelength out of incident light.
The first and second focusing lenses 16 and 17 focus the laser beams having different wavelengths transmitted or reflected by the light transmitting / reflecting mirrors 14 and 15 and derive them on the same optical axis.

  Next, the operation of this embodiment will be described. The semiconductor lasers 11 to 13 emit laser beams having different oscillation wavelengths and the same or different phases. Each of these oscillation wavelengths is a value determined according to the inspection purpose of the inspection object. First, laser light having an oscillation wavelength near λ 1 emitted from the first semiconductor laser 11 is incident on the first light transmission / reflection mirror 14. The light transmitting / reflecting mirror 14 reflects the laser light having a wavelength other than the specific wavelength λ1 to be transmitted, and transmits the laser light having the specific wavelength λ1 according to the filter characteristics of the light transmitting / reflecting mirror 14. The first light transmitting / reflecting mirror 14 removes laser light in an unnecessary wavelength region by reflection.

  On the other hand, for the first light transmission / reflection mirror 14, the second semiconductor laser 12 emits a laser beam having an oscillation wavelength different from the oscillation wavelength of the first semiconductor laser 11 in the vicinity of λ2. The first light transmission / reflection mirror 14 removes laser light other than the specific wavelength λ2 by transmission and reflects only the specific wavelength λ2. For this reason, laser light having a wavelength λ1 and a wavelength λ2 is emitted on a light transmission optical axis A1 connecting the first semiconductor laser 11 and the light transmission / reflection mirror 14.

  The laser beams having the wavelengths λ1 and λ2 are focused by the first focusing lens 16 and are incident on the second light transmission / reflection mirror 15 on the optical axis A1. The second light transmitting / reflecting mirror 15 transmits laser light having specific wavelengths λ1 and λ2.

On the other hand, the third semiconductor laser 13 emits laser light having a wavelength near λ3 that is different from the wavelengths of the laser light emitted by the first semiconductor laser 11 and the second semiconductor laser 2. This laser light is incident on the second light transmitting / reflecting mirror 15, reflects the laser light having the specific wavelength λ3 onto the optical axis A1, and transmits and removes the laser light other than the specific wavelength λ3.
The laser light having the wavelength λ3 is incident on the second focus alignment lens 17 together with the laser light having the wavelengths λ1 and λ2, and is focused and led out on the optical axis A1.

  In this way, the laser beams that have passed through the second focus alignment lens 17 are light that has the same or different phase and different wavelengths such as λ1, λ2, and λ3. The light is emitted serially (in a time division manner) to a predetermined part. The measurement object can be a solid, liquid, gas, or a human body.

  For example, a plurality of positions on the human head are irradiated with a laser beam suitable for any one of the wavelengths λ1, λ2, and λ3 using a plurality of optical fibers, and the absorption rate of the laser light at each wavelength in each region is increased. By measuring, blood flow in the cerebral blood vessel can be measured. The absorption rate of the laser light can be measured by capturing light reflected from each of the parts.

  In addition, by capturing the oxygen state of the brain surface by using near-infrared wavelength spectroscopy, it is possible to use in the field of measuring and monitoring visual, auditory and motor parts in real time and identifying activity states.

  FIG. 2 shows another embodiment of the light output device according to the present invention. In this embodiment, the arrangement of the first semiconductor laser 11 and the second semiconductor laser 12 and the first light transmission / reflection mirror 14 is the same as that shown in FIG. On the other hand, the third semiconductor laser 13 is arranged in a direction in which the A3 direction of the output optical axis of the third semiconductor laser 13 (the direction applied perpendicular to the paper surface) is applied perpendicularly to the output optical axis A2 of the second semiconductor laser 11. .

  The second light transmitting / reflecting mirror 15 reflects the laser light having the wavelength λ3 emitted from the third semiconductor laser 13, and emits the wavelengths λ1, λ2 emitted from the first and second semiconductor lasers 11 and 12. Are guided to an optical axis that coincides with the optical axis A 1 of the first semiconductor laser 11. Note that the first focusing lens 16 and the second focusing lens 17 are omitted here, but these lenses 16 and 17 may be necessary for focusing.

  FIG. 3 shows still another embodiment of the light output device according to the present invention. In this embodiment, the second semiconductor laser 12 and the third semiconductor laser 13 are offset in the optical axis direction at positions sandwiching the emission optical axis A1 of the first semiconductor laser 11. Therefore, the direction of the first light transmitting / reflecting mirror 14 is shown in FIG. 1 so that the second and third semiconductor lasers 12 and 13 derive the laser light in the direction coinciding with the emission optical axis A1. It's the opposite of things.

Also in this case, both the laser beams having the wavelengths λ 1 and λ 2 emitted from the first and second semiconductor lasers 11 and 12 can be guided to the optical axis that coincides with the optical axis A 1 of the first semiconductor laser 11. In the other embodiment, the first focusing lens 16 can be omitted depending on the arrangement of the light transmission / reflection mirrors 14 and 15 and the semiconductor lasers 11, 12, and 13.

  FIG. 4 shows still another embodiment of the light output device according to the present invention. The light output device of this embodiment is an application example of the light output device shown in FIG. The light output device of FIG. 4 is different from the light output device shown in FIG. 3 in which the two independent light transmission / reflection mirrors 14 and 15 are arranged at a predetermined distance. That is, in the light output device of this embodiment, two light transmitting / reflecting mirror members 18a and 18b each having a rectangular plate shape are integrally assembled or integrated with each other at the center. 18 is arranged.

  In the light transmission / reflection mirror 18, the laser light having the specific wavelength λ1 from the first semiconductor laser 11 is transmitted through the light transmission / reflection mirror members 18a and 18b, respectively, and the laser light other than the wavelength λ1 is reflected. The laser light having the wavelength λ2 from the second semiconductor laser 12 is reflected by the light transmission / reflection mirror member 18a, and is transmitted through the light transmission / reflection mirror 18b together with the laser light having the wavelength λ1. The laser light having the wavelength λ3 from the third semiconductor laser 13 is transmitted through the light transmitting / reflecting mirror 18a, reflected by the light transmitting / reflecting mirror 15b, and output together with the laser light having the wavelengths λ1 and λ2.

  Therefore, in the light output device of this embodiment, in addition to the fact that a plurality of laser beams having specific wavelengths can be derived on the same optical axis as described above, and can be efficiently checked against the inspection object, etc., one light transmission -Since it is only necessary to prepare the reflection mirror 18 and install it in the optical system, it is possible to improve the efficiency of the assembly operation of the light output device, reduce the overall size of the device, reduce the occupied space, and reduce costs. It is done.

  In the above, an example in which three semiconductor lasers 11 to 13 are used has been described. However, it is optional to add more semiconductor lasers and light transmission / reflection mirrors according to the number of wavelengths desired to be output. As a result, the state of the measurement object, such as the blood flow state of the blood vessels in the brain, can be measured in more detail and simply by adding an inexpensive light transmission / reflection mirror having wavelength filter characteristics.

  As described above, in this embodiment, the light output device emits a plurality of semiconductor lasers 11, 12, and 13 that emit laser light, and laser light having a specific wavelength that each of these semiconductor lasers 11, 12, and 13 emits. Light transmitting / reflecting mirrors 14 and 15 that are separated from laser beams of other wavelengths and are extracted on the same optical axis, and a focal position of laser light of a specific wavelength extracted through each of these light transmitting and reflecting mirrors 14 and 15 And a plurality of laser beams having different wavelengths are serially output on the same optical axis.

  Accordingly, each of the light transmission / reflection mirrors 14 and 15 collects only laser light of a specific wavelength on the same optical axis and serially outputs it, and irradiates the inspection target with laser light having different wavelengths that are serially output. By analyzing the inspection data corresponding to each wavelength received from the inspection object, it is possible to determine the properties of the inspection object.

  The present invention collects only laser light of a specific wavelength on the same optical axis and serially outputs it, and irradiates the inspection target with laser light having different wavelengths that are serially output. The inspection data can be analyzed. Therefore, it has an effect that it is possible to determine the property of the inspection object from the analysis result, and is useful for a light output device used to measure the property of the inspection object in a wide field.

DESCRIPTION OF SYMBOLS 11 1st semiconductor laser 12 2nd semiconductor laser 13 3rd semiconductor laser 14 1st light transmission / reflection mirror 15 2nd light transmission / reflection mirror 16 1st end point alignment lens 17 2nd focusing lens 18 Light transmission / reflection mirror 18a, 18b Light transmission / reflection mirror member

Claims (2)

A plurality of semiconductor lasers each emitting laser light of a specific wavelength;
A plurality of light transmitting / reflecting mirrors for separating laser light of a specific wavelength emitted by these semiconductor lasers from laser light of other wavelengths and extracting them on one optical axis;
A focusing lens for aligning the focal position of the laser light of a specific wavelength extracted through each of these light transmission / reflection mirrors and deriving it on the optical axis;
With
An optical output device that serially outputs a plurality of laser beams having different wavelengths on the optical axis.   2. The light transmission / reflection mirror has a configuration in which two light transmission / reflection mirror members each having a rectangular plate shape are assembled integrally with each other at a central portion or integrally formed. Light output device.

Images