JP2016051606A - Illuminating device, optical filter, and illuminating system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an illuminating device, an optical filter, and an illuminating system that can cope with various environments.SOLUTION: An illuminating system according to an embodiment includes an illuminating device and an optical filter. The illuminating device includes first to third laser elements. The first to third laser elements emit first to third laser beams having first to third peak wavelengths and full widths at half maximum of 5 nm or less respectively. The optical filter includes a first filter element. The first filter element has first to third transmission wavelength regions having first to third bottom transmission wavelengths and full widths at half maximum of 5 nm or less. Absolute values of differences between the first to third bottom transmission wavelengths and the first to third peak wavelengths are 5 nm or less.SELECTED DRAWING: Figure 1

Description

  Embodiments described herein relate generally to an illumination device, an optical filter, and an illumination system.

  There is a need for a lighting system that can handle various environments. In the illumination system, illumination light is emitted from the illumination device. On the other hand, an optical filter may be used in imaging or astronomical observation.

JP 2010-72494 A

  Embodiments of the present invention provide an illumination device, an optical filter, and an illumination system that can cope with various environments.

  The illumination system according to the embodiment includes an illumination device and an optical filter. The illumination device includes first to third laser elements. The first laser element emits a first laser beam having a first peak wavelength and a full width at half maximum of 5 nanometers or less. The second laser element has a second peak wavelength that is longer than the first peak wavelength and has a difference from the first peak wavelength of 80 nanometers or more and has a full width at half maximum of 5 nanometers or less. Is emitted. The third laser element has a third peak wavelength which is longer than the second peak wavelength and has a difference from the second peak wavelength of 80 nanometers or more and has a full width at half maximum of 5 nanometers or less. Is emitted. The optical filter includes a first filter element. The first filter element includes a first transmission wavelength region having a first bottom transmission wavelength and a full width at half maximum of 5 nanometers or less, and a second transmission wavelength having a second bottom transmission wavelength and a full width at half maximum of 5 nanometers or less. And a third transmission wavelength region having a third bottom transmission wavelength and a full width at half maximum of 5 nanometers or less. The absolute value of the difference between the first bottom transmission wavelength and the first peak wavelength is 5 nanometers or less. The absolute value of the difference between the second bottom transmission wavelength and the second peak wavelength is 5 nanometers or less. The absolute value of the difference between the third bottom transmission wavelength and the third peak wavelength is 5 nanometers or less.

FIG. 1A and FIG. 1B are schematic views illustrating the illumination device according to the first embodiment. FIG. 2A to FIG. 2C are schematic views illustrating the optical filter according to the first embodiment. FIG. 3A and FIG. 3B are schematic views illustrating the illumination device according to the second embodiment. FIG. 4A to FIG. 4C are schematic views illustrating the optical filter according to the second embodiment. It is a schematic diagram which illustrates another illuminating device which concerns on embodiment. It is a schematic diagram which illustrates another illuminating device which concerns on embodiment. It is a typical sectional view which illustrates an optical filter concerning an embodiment. It is a schematic diagram which illustrates the illumination system which concerns on 3rd Embodiment.

Embodiments of the present invention will be described below with reference to the drawings.
The drawings are schematic or conceptual, and the relationship between the thickness and width of each part, the size ratio between the parts, and the like are not necessarily the same as actual ones. Further, even when the same part is represented, the dimensions and ratios may be represented differently depending on the drawings.
Note that, in the present specification and each drawing, the same elements as those described above with reference to the previous drawings are denoted by the same reference numerals, and detailed description thereof is omitted as appropriate.

(First embodiment)
FIG. 1A and FIG. 1B are schematic views illustrating the illumination device according to the first embodiment.
FIG. 1A is a perspective view. FIG. 1B is a graph illustrating characteristics of the lighting device. In FIG. 1B, the vertical axis represents the light intensity Int1 (arbitrary unit), and the horizontal axis represents the wavelength λ (nanometer: nm).

  As shown to Fig.1 (a), in the illuminating device 110 which concerns on this embodiment, the 1st laser element 11, the 2nd laser element 12, and the 3rd laser element 13 are provided. In this example, the first laser element 11, the second laser element 12, and the third laser element 13 are provided in the housing 18.

  The first laser element 11 emits the first laser beam LL1. The second laser element 12 emits the second laser beam LL2. The third laser element 13 emits the third laser light LL3.

  As shown in FIG. 1B, the first laser beam LL1 has a first peak wavelength λe1. The second laser light LL2 has a second peak wavelength λe2. The second peak wavelength λe2 is longer than the first peak wavelength λe1. The difference between the second peak wavelength λe2 and the first peak wavelength λe1 is, for example, 50 nm or more. The third laser beam LL3 has a third peak wavelength λe3. The third peak wavelength λe3 is longer than the second peak wavelength λe2. The difference between the third peak wavelength λe3 and the second peak wavelength λe2 is, for example, 50 nm or more.

  As shown in FIG. 1B, the first laser beam LL1 has a first peak intensity Ie1 at the first peak wavelength λe1. The second laser beam LL2 has a second peak intensity Ie2 at the second peak wavelength λe2. The third laser beam LL3 has a third peak intensity Ie3 at the third peak wavelength λe3.

  The first peak intensity Ie1 of the first laser beam LL1 at the first peak wavelength λe1 is higher than the intensity of the first laser beam LL1 at wavelengths other than the first peak wavelength λe1. The second peak intensity Ie2 of the second laser beam LL2 at the second peak wavelength λe2 is higher than the intensity of the second laser beam LL2 at wavelengths other than the second peak wavelength λe2. The third peak intensity Ie3 of the third laser beam LL3 at the third peak wavelength λe3 is higher than the intensity of the third laser beam LL3 at wavelengths other than the third peak wavelength λe3.

  In the embodiment, these peak intensities may be the same or different from each other. In this example, the second peak intensity Ie2 is higher than the first peak intensity Ie1. The second peak intensity Ie2 is higher than the third peak intensity Ie3.

  Each of the full width at half maximum We1 of the first laser beam LL1, the full width at half maximum We2 of the second laser beam LL2, and the full width at half maximum We3 of the third laser beam LL3 is, for example, 10 nm or less.

  In the first laser beam LL1, the light intensity is ½ or more of the first peak intensity Ie1 in the wavelength range of the full width at half maximum We1. In the second laser beam LL2, the light intensity is ½ or more of the second peak intensity Ie2 in the wavelength range of the full width at half maximum We2. In the third laser beam LL3, the light intensity is ½ or more of the third peak intensity Ie3 in the wavelength range of the full width at half maximum We3.

  For example, the first laser beam LL1 is blue, the second laser beam LL2 is green, and the third laser beam LL3 is red. By setting the first peak wavelength λe1, the second peak wavelength λe2, and the third peak wavelength λe3 in this way, the light obtained by combining the first laser light LL1, the second laser light LL2, and the third laser light LL3. Becomes white.

FIG. 2A to FIG. 2C are schematic views illustrating the optical filter according to the first embodiment.
FIG. 2A is a perspective view. FIG. 2B is a graph illustrating characteristics of the optical filter. FIG. 2B illustrates the relationship between wavelength and transmittance. The vertical axis in FIG. 2B is the transmittance Tr. The horizontal axis is the wavelength λ (nm). FIG. 2C is a graph illustrating characteristics of the optical filter. FIG. 2C illustrates the relationship between the wavelength and the reflectance. The vertical axis in FIG. 2C is the reflectance Rf. The horizontal axis is the wavelength λ (nm).

  As shown in FIG. 2A, the first filter element 21 is provided in the optical filter 210 according to the present embodiment. In the example illustrated in FIG. 2A, the optical filter 210 further includes a frame body 28. The first filter element 21 has, for example, a plate shape. The first filter element 21 is attached to, for example, the camera light receiving unit 310 via the frame body 28. The light incident on the optical filter 210 passes through the optical filter 210 and enters the camera light receiving unit 310.

  As shown in FIG. 2B, the first filter element 21 has a first transmission wavelength region Rt1, a second transmission wavelength region Rt2, and a third transmission wavelength region Rt3.

The first transmission wavelength region Rt1 has a first bottom transmission wavelength λt1.
The second transmission wavelength region Rt2 has a second bottom transmission wavelength λt2. The second bottom transmission wavelength λt2 is longer than the first bottom transmission wavelength λt1. The difference between the second bottom transmission wavelength λt2 and the first bottom transmission wavelength λt1 is, for example, 50 nm or more.
The third transmission wavelength region Rt3 has a third bottom transmission wavelength λt3. The third bottom transmission wavelength λt3 is longer than the second bottom transmission wavelength λt2. The difference between the third bottom transmission wavelength λt3 and the second bottom transmission wavelength λt2 is, for example, 50 nm or more.

  As shown in FIG. 2B, the first transmission wavelength region Rt1 has a first bottom transmittance It1 at the first bottom transmission wavelength λt1. The second transmission wavelength region Rt2 has a second bottom transmittance It2 at the second bottom transmission wavelength λt2. The third transmission wavelength region Rt3 has a third bottom transmittance It3 at the third bottom transmission wavelength λt3.

The first bottom transmittance It1 at the first bottom transmission wavelength λt1 in the first transmission wavelength region Rt1 is lower than the transmittance at wavelengths other than the first bottom transmission wavelength λt1 in the first transmission wavelength region Rt1.
The second bottom transmittance It2 at the second bottom transmission wavelength λt2 in the second transmission wavelength region Rt2 is lower than the transmittance at wavelengths other than the second bottom transmission wavelength λt2 in the second transmission wavelength region Rt2.
The third bottom transmittance It3 at the third bottom transmission wavelength λt3 in the third transmission wavelength region Rt3 is lower than the transmittance at wavelengths other than the third bottom transmission wavelength λt3 in the third transmission wavelength region Rt3.

  In the embodiment, these bottom transmittances may be the same or different from each other. In this example, the second bottom transmittance It2 is lower than the first bottom transmittance It1. The second bottom transmittance It2 is lower than the third bottom transmittance It3.

  The full width at half maximum Wt1 of the first transmission wavelength region Rt1 is, for example, 10 nm or less. The full width at half maximum Wt2 of the second transmission wavelength region Rt2 is, for example, 10 nm or less. The full width at half maximum Wt3 of the third transmission wavelength region Rt3 is, for example, 10 nm or less.

  In the wavelength range of the full width at half maximum Wt1, the transmittance is {It1 + (1-It1) / 2} or less. In the wavelength range of the full width at half maximum Wt2, the transmittance is {It2 + (1-It2) / 2} or less. In the wavelength range of the full width at half maximum Wt3, the transmittance is {It3 + (1-It3) / 2} or less.

  For example, the first bottom transmission wavelength λt1 is a blue wavelength. The second bottom transmission wavelength λt2 is a green wavelength. The third bottom transmission wavelength λt3 is a red wavelength.

  In this example, the first bottom transmission wavelength λt1 corresponds to the first peak wavelength λe1 of the first laser light LL1. The second bottom transmission wavelength λt2 corresponds to the second peak wavelength λe2 of the second laser light LL2. The third bottom transmission wavelength λt3 corresponds to the third peak wavelength λe3 of the third laser light LL3.

  In the embodiment, for example, the absorption rate in the optical filter 210 is low and can be ignored. At this time, the sum of the transmittance and the reflectance is substantially 1.

  As shown in FIG. 2C, the first filter element 21 has a first reflection wavelength region Rr1, a second reflection wavelength region Rr2, and a third reflection wavelength region Rr3.

The first reflection wavelength region Rr1 has a first peak reflection wavelength λr1.
The second reflection wavelength region Rr2 has a second peak reflection wavelength λr2. The second peak reflection wavelength λr2 is longer than the first peak reflection wavelength λr1. The difference between the second peak reflection wavelength λr2 and the first peak reflection wavelength λr1 is, for example, 50 nm or more.
The third reflection wavelength region Rr3 has a third peak reflection wavelength λr3. The third peak reflection wavelength λr3 is longer than the second peak reflection wavelength λr2. The difference between the third peak reflection wavelength λr3 and the second peak reflection wavelength λr2 is, for example, 50 nm or more.

  As shown in FIG. 2B, the first reflection wavelength region Rr1 has a first peak reflectance Ir1 at the first peak reflection wavelength λr1. The second reflection wavelength region Rr2 has a second peak reflectance Ir2 at the second peak reflection wavelength λr2. The third reflection wavelength region Rr3 has a third peak reflectance Ir3 at the third peak reflection wavelength λr3.

The first peak reflectance Ir1 at the first peak reflection wavelength λr1 is higher than the reflectance at wavelengths other than the first peak reflection wavelength λr1 in the first reflection wavelength region Rr1.
The second peak reflectance Ir2 at the second peak reflection wavelength λr2 is higher than the reflectance at wavelengths other than the second peak reflection wavelength λr2 in the second reflection wavelength region Rr2.
The third peak reflectance Ir3 at the third peak reflection wavelength λr3 is higher than the reflectance at wavelengths other than the third peak reflection wavelength λr3 in the third reflection wavelength region Rr3.

  In the embodiment, these reflectances may be the same or different from each other. In this example, the second peak reflectance Ir2 is higher than the first peak reflectance Ir1. The second peak reflectance Ir2 is higher than the third peak reflectance Ir3.

  The full width at half maximum Wr1 of the first reflection wavelength region Rr1 is, for example, 10 nm or less. The full width at half maximum Wr2 of the second reflection wavelength region Rr2 is, for example, 10 nm or less. The full width at half maximum Wr3 of the third reflection wavelength region Rr3 is, for example, 10 nm or less.

  In the wavelength range of the full width at half maximum Wr1, the reflectance is ½ or more of the first peak reflectance Ir1. In the wavelength range of the full width at half maximum Wr2, the reflectance is ½ or more of the second peak reflectance Ir2. In the wavelength range of the full width at half maximum Wr3, the reflectance is ½ or more of the third peak reflectance Ir3.

  In an illumination environment using the illumination device 110 described above, an object in the illumination environment is naturally observed.

  On the other hand, a specific object or the like is observed using the optical filter 210 described above. The specific object is, for example, a celestial body. By observing through the optical filter 210, the light component of the bottom transmission wavelength of the optical filter 210 is substantially excluded. Then, light components other than the bottom transmission wavelength pass through the optical filter 210. For example, at least part of the light from the celestial body passes through the optical filter 210. The light that has passed through the optical filter 210 reaches the camera light receiving unit 310, for example. The illumination light from the illumination device 110 is not substantially incident on the camera light receiving unit 310. For example, light from a celestial body that has passed through the optical filter 210 is incident on the camera light receiving unit 310. That is, by selectively attenuating the illumination light from the illuminating device 110, it is possible to efficiently observe the light intended for observation (for example, light from a celestial body).

  For example, the optical filter 210 may be used in combination with a spectacle lens. In this case, the user using the glasses cannot substantially perceive the illumination light from the illumination device 110. That is, a dark image is perceived. At this time, the user can perceive light having a wavelength excluding the wavelength component (peak wavelength) of the illumination light from the illumination device 110. That is, it is possible to easily perceive a light emitter or reflector (object) having a wavelength characteristic different from the illumination light from the illumination device 110. That is, it can be perceived while suppressing the influence of the illumination light from the illumination device 110.

  For example, if streetlights brighten the night sky at night, it will be difficult to see the stars. That is, light pollution occurs. For this reason, places where stars can be observed are decreasing. In an observation device with a high light gathering power, light pollution in the background of the night sky becomes observation noise.

  The present embodiment focuses on this problem. According to the embodiment, the illumination device 110 is introduced into a specific area, and observation and observation are performed using the optical filter 210. Thereby, in that area, the observability and observability of the celestial bodies are remarkably improved compared to other areas. In the illumination device 110, the use of a three-wavelength laser can suppress light pollution while maintaining the quality as illumination.

  For example, the illumination device 110 is used as a street light, and the optical filter 210 is used in an astronomical telescope that observes astronomical objects. Thereby, an astronomical object can be observed without being affected by the illumination light from the illumination device 110.

  In the embodiment, the absolute value of the difference between the first bottom transmission wavelength λt1 and the first peak wavelength λe1 is, for example, 5 nm or less. More preferably, it is 3 nm or less. The absolute value of the difference between the second bottom transmission wavelength λt2 and the second peak wavelength λe2 is, for example, 5 nm or less. More preferably, it is 3 nm or less. The absolute value of the difference between the third bottom transmission wavelength λt3 and the third peak wavelength λe3 is, for example, 5 nm or less. More preferably, it is 3 nm or less.

  For example, the bottom transmission wavelength and the peak wavelength are substantially the same. When the difference is small, for example, there is little leakage of laser light. And the loss of light can be suppressed. The background becomes dark and the contrast of the observation object increases. Thereby, for example, observation with high S / N can be performed.

  In the embodiment, the second peak wavelength λe2 is longer than the first peak wavelength λe1. The difference between the second peak wavelength λe2 and the first peak wavelength λe1 is 50 nm or more. More preferably, it is 80 nm or more. The third peak wavelength λe3 is longer than the second peak wavelength λe2. The difference between the third peak wavelength λe3 and the second peak wavelength λe2 is 50 nm or more. More preferably, it is 80 nm or more.

  The first peak wavelength λe1, the second peak wavelength λe2, and the third peak wavelength λe3 are set differently. Therefore, the combined light of the first laser beam LL1, the second laser beam LL2, and the third laser beam LL3 includes, for example, a plurality of colors. The illumination light from the illumination device 110 can identify a plurality of colors of the object.

  In order to increase the identifiable color, each of the first peak intensity Ie1, the second peak intensity Ie2, and the third peak intensity Ie3 may be adjusted.

  For example, the first laser light LL1 is blue, the second laser light LL2 is green, and the third laser light LL3 is red. In this case, when the first laser beam LL1, the second laser beam LL2, and the third laser beam LL3 are combined, the color becomes white. High quality is obtained in the illumination of the illumination device 110. The illumination light from the illumination device 110 increases the types of colors that can be identified. The fineness of color identification is improved.

  In the embodiment, a laser element is used. For example, a semiconductor laser is used as the laser element. In the laser element, the light emission of the light emitter is very small. For this reason, compared with LED (Light Emitting Diode: light emitting diode), a high light density (high brightness) is obtained. On the other hand, in the LED, there is heat generation of the element and heat generation of the phosphor. Due to these heats, the temperature of the device and the phosphor increases, and the efficiency decreases. In a laser element (for example, a laser diode: a semiconductor laser), laser light is irradiated onto a scatterer, and light scattered by the scatterer can be used. Thereby, heat_generation | fever can be made small. For example, in an LED, even if a condensing lens or the like is used, the luminance cannot be made higher than that of a light source. On the other hand, the luminance of the laser element is very high. Laser light is coherent and has high directivity. By using a scatterer, high luminance can be obtained while reducing coherency and directivity. The risk of laser light can be reduced by scattering.

In the embodiment, the full width at half maximum We1 of the first laser beam LL1 is, for example, 10 nm or less. More preferably, it is 5 nm or less. The full width at half maximum We2 of the second laser light LL2 is, for example, 10 nm or less. More preferably, it is 5 nm or less. The full width at half maximum We3 of the third laser beam LL3 is, for example, 10 nm or less. More preferably, it is 5 nm or less.
By narrowing the full width at half maximum in this way, a high S / N can be maintained when the first laser beam LL1, the second laser beam LL2, and the third laser beam LL3 are attenuated by the optical filter.

  The bandwidth of the first laser beam LL1 is, for example, within 10 nm. More preferably, it is within 5 nm. The bandwidth of the second laser light LL2 is, for example, within 10 nm. More preferably, it is within 5 nm. The bandwidth of the third laser light LL3 is, for example, within 10 nm. More preferably, it is within 5 nm.

  In the embodiment, the second bottom transmission wavelength λt2 is longer than the first bottom transmission wavelength λt1. The difference between the second bottom transmission wavelength λt2 and the first bottom transmission wavelength λt1 is, for example, 50 nm or more. More preferably, it is 80 nm or more. The third bottom transmission wavelength λt3 is longer than the second bottom transmission wavelength λt2. The difference between the third bottom transmission wavelength λt3 and the second bottom transmission wavelength λt2 is, for example, 50 nm or more. More preferably, it is 80 nm or more.

  The first bottom transmission wavelength λt1 corresponds to the first peak wavelength λe1 of the first laser beam LL1. The second bottom transmission wavelength λt2 corresponds to the second peak wavelength λe2 of the second laser light LL2. The third bottom transmission wavelength λt3 corresponds to the third peak wavelength λe3 of the third laser light LL3. The first filter element 21 attenuates the first laser light LL1, the second laser light LL2, and the third laser light LL3.

  In the embodiment, the full width at half maximum Wt1 of the first transmission wavelength region Rt1 is, for example, 10 nm or less. More preferably, it is 5 nm or less. The full width at half maximum Wt2 of the second transmission wavelength region Rt2 is, for example, 10 nm or less. More preferably, it is 5 nm or less. The full width at half maximum Wt3 of the third transmission wavelength region Rt3 is, for example, 10 nm or less. More preferably, it is 5 nm or less. Thus, since the optical filter 210 is set to have a narrow transmission wavelength region, light loss can be suppressed.

The illumination device and the filter according to the embodiment are used, for example, in the vicinity of an astronomical observation facility where light pollution is a problem.
According to this embodiment, for example, light pollution can be reduced. And high quality illumination light is obtained. According to the embodiment, it is possible to provide an illumination device and an optical filter that can cope with various environments.

(Second Embodiment)
FIG. 3A and FIG. 3B are schematic views illustrating the illumination device according to the second embodiment.
FIG. 3A is a perspective view. FIG. 3B is a graph illustrating characteristics of the lighting device.
In FIG. 3B, the vertical axis represents the light intensity Int2 (arbitrary unit), and the horizontal axis represents the wavelength λ (nm).

  As shown in FIG. 3A, in the illumination device 111 according to this embodiment, in addition to the first laser element 11, the second laser element 12, and the third laser element 13, a fourth laser element 14 and a fifth laser are provided. An element 15 and a sixth laser element 16 and a laser control unit 38 are further provided. In this example, the fourth laser element 14, the fifth laser element 15, and the sixth laser element 16 are provided in the housing 18.

The fourth laser element 14 emits the fourth laser light LL4. The fifth laser element 15 emits the fifth laser beam LL5. The sixth laser element 16 emits the sixth laser beam LL6.
In the following description, the first laser beam LL1, the second laser beam LL2, and the third laser beam LL3 are collectively referred to as a “first laser beam group”. The fourth laser beam LL4, the fifth laser beam LL5, and the sixth laser beam LL6 are collectively referred to as a “second laser beam group”.

  As shown in FIG. 3B, the fourth laser beam LL4 has a fourth peak wavelength λe4. The absolute value of the difference between the fourth peak wavelength λe4 and the first peak wavelength λe1 is, for example, not less than 4 nm and not more than 80 nm. The fifth laser beam LL5 has a fifth peak wavelength λe5. The absolute value of the difference between the fifth peak wavelength λe5 and the second peak wavelength λe2 is, for example, not less than 4 nm and not more than 80 nm. The sixth laser beam LL6 has a sixth peak wavelength λe6. The absolute value of the difference between the sixth peak wavelength λe6 and the third peak wavelength λe3 is, for example, not less than 4 nm and not more than 80 nm.

  The fourth peak intensity Ie4 of the fourth laser beam LL4 at the fourth peak wavelength λe4 is higher than the intensity of the fourth laser beam LL4 at wavelengths other than the fourth peak wavelength λe4. The fifth peak intensity Ie5 of the fifth laser beam LL5 at the fifth peak wavelength λe5 is higher than the intensity of the fifth laser beam LL5 at wavelengths other than the fifth peak wavelength λe5. The sixth peak intensity Ie6 of the sixth laser beam LL6 at the sixth peak wavelength λe6 is higher than the intensity of the sixth laser beam LL6 at wavelengths other than the sixth peak wavelength λe6.

  In FIG. 3B, the fourth laser beam LL4 has a fourth peak intensity Ie4 at the fourth peak wavelength λe4. The fifth laser beam LL5 has a fifth peak intensity Ie5 at the fifth peak wavelength λe5. The sixth laser beam LL6 has a sixth peak intensity Ie6 at the sixth peak wavelength λe6.

  In the embodiment, these peak intensities may be the same or different from each other. In this example, the fifth peak intensity Ie5 is higher than the fourth peak intensity Ie4. The fifth peak intensity Ie5 is higher than the sixth peak intensity Ie6.

  Each of the full width at half maximum We4 of the fourth laser beam LL4, the full width at half maximum We5 of the fifth laser beam LL5, and the full width at half maximum We6 of the sixth laser beam LL6 is, for example, 10 nm or less.

  In the fourth laser beam LL4, the light intensity is ½ or more of the fourth peak intensity Ie4 in the wavelength range of the full width at half maximum We4. In the fifth laser light LL5, the light intensity is ½ or more of the second peak intensity Ie5 in the wavelength range of the full width at half maximum We5. In the sixth laser beam LL6, the light intensity is ½ or more of the sixth peak intensity Ie6 in the wavelength range of the full width at half maximum We6.

  For example, the fourth laser beam LL4 is blue, the fifth laser beam LL5 is green, and the sixth laser beam LL6 is red. By setting the fourth peak wavelength λe4, the fifth peak wavelength λe5, and the sixth peak wavelength λe6 in this way, light in which the fourth laser light LL4, the fifth laser light LL5, and the sixth laser light LL6 are combined. Becomes white.

The laser control unit 38 controls the emission of laser light from each laser element.
In the first state, the laser control unit 38, for example, causes the first laser element 11 to emit the first laser light LL1, causes the second laser element 12 to emit the second laser light LL2, and causes the third laser element 13 to emit the first laser light LL2. Three laser beams LL3 are emitted.
In the second state, the laser control unit 38, for example, causes the fourth laser element 14 to emit the fourth laser light LL4, causes the fifth laser element 15 to emit the fifth laser light LL5, and causes the sixth laser element 16 to 6 laser light LL6 is emitted.

  The intensity of the first laser beam L1 emitted from the first laser element 11 in the second state is lower than the intensity of the first laser beam L1 emitted from the first laser element 11 in the first state. The intensity of the second laser light L2 emitted from the second laser element 12 in the second state is lower than the intensity of the second laser light L2 emitted from the second laser element 12 in the first state. The intensity of the third laser light L3 emitted from the third laser element 13 in the second state is lower than the intensity of the third laser light L3 emitted from the third laser element 13 in the first state. For example, in the second state, the first laser element 11 does not emit the first laser light L1. For example, in the second state, the second laser element 12 does not emit the second laser light L2. For example, in the second state, the third laser element 13 does not emit the third laser light L3.

  The intensity of the fourth laser light L4 emitted from the fourth laser element 14 in the first state is lower than the intensity of the fourth laser light L4 emitted from the fourth laser element 14 in the second state. The intensity of the fifth laser beam L5 emitted from the fifth laser element 15 in the first state is lower than the intensity of the fifth laser beam L5 emitted from the fifth laser element 15 in the second state. The intensity of the sixth laser light L6 emitted from the sixth laser element 16 in the first state is lower than the intensity of the sixth laser light L6 emitted from the sixth laser element 16 in the second state. For example, in the first state, the fourth laser element 14 does not emit the fourth laser light L4. For example, in the first state, the fifth laser element 15 does not emit the fifth laser beam L5. For example, in the first state, the sixth laser element 16 does not emit the sixth laser beam L6.

  The laser control unit 38 emits the first laser beam group in the first state, for example, does not emit the second laser beam group. The laser control unit 38 emits the second laser beam group in the second state, for example, does not emit the first laser beam group.

FIG. 4A to FIG. 4C are schematic views illustrating the optical filter according to the second embodiment.
FIG. 4A is a perspective view. FIG. 4B is a graph illustrating characteristics of the optical filter. FIG. 4B illustrates the relationship between wavelength and transmittance. The vertical axis | shaft of FIG.4 (b) is the transmittance | permeability Tr. The horizontal axis is the wavelength λ (nm). FIG. 4C is a graph illustrating characteristics of the optical filter. FIG. 4C illustrates the relationship between the wavelength and the reflectance. The vertical axis in FIG. 4C is the reflectance Rf. The horizontal axis is the wavelength λ (nm).

  As shown in FIG. 4A, the second filter element 22 is provided in the optical filter 211 according to the present embodiment. In the example illustrated in FIG. 4A, the optical filter 211 further includes a frame body 28. The second filter element 22 has a plate shape, for example. For example, the second filter element 21 is attached to the camera light receiving unit 310 via the frame body 28. The light incident on the optical filter 211 passes through the optical filter 211 and enters the camera light receiving unit 310.

As shown in FIG. 4B, the second filter element 21 has a fourth transmission wavelength region Rt4, a fifth transmission wavelength region Rt5, and a sixth transmission wavelength region Rt6.
The fourth transmission wavelength region Rt4 has a fourth bottom transmission wavelength λt4.
The absolute value of the difference between the fourth bottom transmission wavelength λt4 and the first bottom transmission wavelength λt1 is, for example, 4 nm or more and 80 nm or less.
The fifth transmission wavelength region Rt5 has a fifth bottom transmission wavelength λt5.
The absolute value of the difference between the fifth bottom transmission wavelength λt5 and the second bottom transmission wavelength λt2 is, for example, not less than 4 nm and not more than 80 nm.
The sixth transmission wavelength region Rt6 has a sixth bottom transmission wavelength λt6.
The absolute value of the difference between the sixth bottom transmission wavelength λt6 and the third bottom transmission wavelength λt3 is, for example, not less than 4 nm and not more than 80 nm.

  As shown in FIG. 4B, the fourth transmission wavelength region Rt4 has a fourth bottom transmittance It4 at the fourth bottom transmission wavelength λt4. The fifth transmission wavelength region Rt5 has the fifth bottom transmittance It5 at the fifth bottom transmission wavelength λt5. The sixth transmission wavelength region Rt6 has a sixth bottom transmittance It6 at the sixth bottom transmission wavelength λt6.

The fourth bottom transmittance It4 at the fourth bottom transmission wavelength λt4 in the fourth transmission wavelength region Rt4 is lower than the transmittance at wavelengths other than the fourth bottom transmission wavelength λt4 in the fourth transmission wavelength region Rt4.
The fifth bottom transmittance It5 at the fifth bottom transmission wavelength λt5 in the fifth transmission wavelength region Rt5 is lower than the transmittance at wavelengths other than the fifth bottom transmission wavelength λt5 in the fifth transmission wavelength region Rt5.
The sixth bottom transmittance It6 at the sixth bottom transmission wavelength λt6 in the sixth transmission wavelength region Rt6 is lower than the transmittance at wavelengths other than the sixth bottom transmission wavelength λt6 in the sixth transmission wavelength region Rt6.

  The fourth bottom transmission wavelength λt4 corresponds to the fourth peak wavelength λe4 of the fourth laser light LL4. The fifth bottom transmission wavelength λt5 corresponds to the fifth peak wavelength λe5 of the fifth laser beam LL5. The sixth bottom transmission wavelength λt6 corresponds to the sixth peak wavelength λe6 of the sixth laser beam LL6. The second filter element 22 attenuates the fourth laser light LL4, the fifth laser light LL5, and the sixth laser light LL6.

  The absolute value of the difference between the fourth bottom transmission wavelength λt4 and the fourth peak wavelength λe4 is, for example, 5 nm or less. More preferably, it is 3 nm or less. The absolute value of the difference between the fifth bottom transmission wavelength λt5 and the fifth peak wavelength λe5 is, for example, 5 nm or less. More preferably, it is 3 nm or less. The absolute value of the difference between the sixth bottom transmission wavelength λt6 and the sixth peak wavelength λe6 is, for example, 5 nm or less. More preferably, it is 3 nm or less.

In the embodiment, in the illumination device 111, the emission of the first laser beam group and the emission of the second laser beam group can be switched as necessary.
In the embodiment, for example, either the optical filter 210 or the optical filter 211 is used.

  For example, the illumination device 111 is used as a street light, and either the optical filter 210 or the optical filter 211 is used for an astronomical telescope that observes astronomical objects. An astronomical object can be imaged substantially without being affected by illumination light from the illumination device 111.

  For example, when the first laser beam group is emitted from the illumination device 111, the observer uses the optical filter 210. Thereby, it can observe in the state which the influence of the 1st laser beam group reduced. When the second laser beam group is emitted from the illumination device 111, the observer uses the optical filter 211. Thereby, it can observe in the state which reduced the influence of the 2nd laser beam group.

  When light from an observation target (for example, a star) has a wavelength component that overlaps with the wavelength of the first laser beam group (first to third peak wavelengths λe1 to 3), the light from the target (for example, a star) Separation from one laser beam group becomes difficult. For this reason, it is difficult to observe an object (for example, a star). The first laser beam group and the second laser beam group are used, and they are switched and used. For example, light from an object (for example, a star) does not substantially overlap with the wavelength of the second laser beam group (fourth to sixth peak wavelengths λe4 to 6). Separation of the light from the object (for example, a star) and the first laser beam group is facilitated. Observation of objects (eg stars) becomes easy.

  That is, the first RBG laser illumination and the second RGB laser illumination having a peak wavelength different from that of the first RGB laser illumination are used. Then, a first filter that reflects the light of the first RGB laser illumination and a second filter that reflects the light of the second RGB laser illumination are used. The first and second RGB laser illuminations can be switched. The first and second filters (first and second filter elements 21 and 22) can be switched. When the first RGB laser illumination is irradiated, the first filter is used. When the second RGB laser illumination is irradiated, the second filter is used.

  Of the light emitted from the celestial body to be observed, when the first peak wavelength λe1 is included in the light to be observed, the light to be observed cannot be observed using the optical filter 210. In this case, the second laser beam group is emitted and the first laser beam group is not emitted, and the optical filter 211 is used to attenuate the second laser beam group. Thereby, it is possible to observe the light to be observed while using the laser beam group as illumination.

  In the first state, for example, the first laser beam group may be emitted and the second laser beam group may be emitted with a weak output. In this case, even if the second laser beam group is used as illumination, for example, light damage can be suppressed. In the second state, for example, the second laser beam group may be emitted and the first laser beam group may be emitted with a weak output. In this case, even if the first laser beam group is used as illumination, for example, light damage can be suppressed.

  In the embodiment, the bottom transmittances may be the same or different from each other. In this example, the fourth bottom transmittance It4 is lower than the fifth bottom transmittance It5. The sixth bottom transmittance It6 is lower than the fifth bottom transmittance It5.

  The full width at half maximum Wt4 of the fourth transmission wavelength region Rt4 is, for example, 10 nm or less. The full width at half maximum Wt5 of the fifth transmission wavelength region Rt5 is, for example, 10 nm or less. The full width at half maximum Wt6 of the sixth transmission wavelength region Rt6 is, for example, 10 nm or less.

  In the wavelength range of the full width at half maximum Wt4, the transmittance is {It4 + (1-It4) / 2} or less. In the wavelength range of the full width at half maximum Wt5, the transmittance is {It5 + (1-It5) / 2} or less. In the wavelength range of the full width at half maximum Wt6, the transmittance is {It6 + (1-It6) / 2} or less.

  For example, the fourth bottom transmission wavelength λt4 is a blue wavelength. The fifth bottom transmission wavelength λt5 is a green wavelength. The sixth bottom transmission wavelength λt6 is a red wavelength.

  In this example, the fourth bottom transmission wavelength λt4 corresponds to the fourth peak wavelength λe4 of the fourth laser light LL4. The fifth bottom transmission wavelength λt5 corresponds to the fifth peak wavelength λe5 of the fifth laser beam LL5. The sixth bottom transmission wavelength λt6 corresponds to the sixth peak wavelength λe6 of the sixth laser beam LL6.

  In the embodiment, for example, the absorption rate in the optical filter 211 is low and can be ignored. At this time, the sum of the transmittance and the reflectance is substantially 1.

  As shown in FIG. 4C, the second filter element 22 has a fourth reflection wavelength region Rr4, a fifth reflection wavelength region Rr5, and a sixth reflection wavelength region Rr6.

The fourth reflection wavelength region Rr4 has a fourth peak reflection wavelength λr4.
The absolute value of the difference between the fourth peak reflection wavelength λr4 and the first peak reflection wavelength λr1 is, for example, 4 nm or more and 80 nm or less.
The fifth reflection wavelength region Rr5 has a fifth peak reflection wavelength λr5.
The absolute value of the difference between the fifth peak reflection wavelength λr5 and the second peak reflection wavelength λr2 is, for example, 4 nm or more and 80 nm or less.
The sixth reflection wavelength region Rr6 has a sixth peak reflection wavelength λr6.
The absolute value of the difference between the sixth peak reflection wavelength λr6 and the third peak reflection wavelength λr3 is, for example, 4 nm or more and 80 nm or less.

  In FIG. 4C, the fourth reflection wavelength region Rr4 has a fourth peak reflectance Ir4 at the fourth peak reflection wavelength λr4. The fifth reflection wavelength region Rr5 has a fifth peak reflectance Ir5 at the fifth peak reflection wavelength λr5. The sixth reflection wavelength region Rr6 has a sixth peak reflectance Ir6 at the sixth peak reflection wavelength λr6.

The fourth peak reflectance Ir4 at the fourth peak reflection wavelength λr4 is higher than the reflectance at wavelengths other than the fourth peak reflection wavelength λr4 in the fourth reflection wavelength region Rr4.
The fifth peak reflectance Ir5 at the fifth peak reflection wavelength λr5 is higher than the reflectance at wavelengths other than the fifth peak reflection wavelength λr5 in the fifth reflection wavelength region Rr5.
The sixth peak reflectance Ir6 at the sixth peak reflection wavelength λr6 is higher than the reflectance at wavelengths other than the sixth peak reflection wavelength λr6 in the sixth reflection wavelength region Rr6.

  In the embodiment, these reflectances may be the same or different from each other. In this example, the fifth peak reflectance Ir5 is lower than the fourth peak reflectance Ir4. The fifth peak reflectance Ir5 is lower than the sixth peak reflectance Ir6.

  The full width at half maximum Wr4 of the fourth reflection wavelength region Rr4 is, for example, 10 nm or less. The full width at half maximum Wr5 of the fifth reflection wavelength region Rr5 is, for example, 10 nm or less. The full width at half maximum Wr6 of the sixth reflection wavelength region Rr6 is, for example, 10 nm or less.

  In the wavelength range of the full width at half maximum Wr4, the reflectance is ½ or more of the fourth peak reflectance Ir4. In the wavelength range of the full width at half maximum Wr5, the reflectance is ½ or more of the fifth peak reflectance Ir5. In the wavelength range of the full width at half maximum Wr6, the reflectance is ½ or more of the sixth peak reflectance Ir6.

  In this example, the fourth peak reflection wavelength λr4 corresponds to the fourth peak wavelength λe4 of the fourth laser beam LL4. The fifth peak reflection wavelength λr5 corresponds to the fifth peak wavelength λe5 of the fifth laser beam LL5. The sixth peak reflection wavelength λr6 corresponds to the sixth peak wavelength λe6 of the sixth laser beam LL6.

  In the embodiment, the absolute value of the difference between the fourth peak wavelength λe4 and the first peak wavelength λe1 is, for example, not less than 4 nm and not more than 80 nm. More preferably, it is 6 nm or more and 60 nm or less. The absolute value of the difference between the fifth peak wavelength λe5 and the second peak wavelength λe2 is, for example, not less than 4 nm and not more than 80 nm. More preferably, it is 6 nm or more and 60 nm or less. The absolute value of the difference between the sixth peak wavelength λe6 and the third peak wavelength λe3 is, for example, not less than 4 nm and not more than 80 nm. More preferably, it is 6 nm or more and 60 nm or less.

  The fourth peak wavelength λe4, the fifth peak wavelength λe5, and the sixth peak wavelength λe6 are set differently. Therefore, the combined light of the fourth laser beam LL4, the fifth laser beam LL5, and the sixth laser beam LL6 includes, for example, a plurality of colors. The illumination light from the illumination device 111 can identify a plurality of colors of the object.

  In order to increase the identifiable color, each of the fourth peak wavelength λe4, the fifth peak wavelength λe5, and the sixth peak wavelength λe6 may be adjusted.

  For example, the fourth laser light LL4 is blue, the fifth laser light LL5 is green, and the sixth laser light LL6 is red. In this case, when the fourth laser beam LL4, the fifth laser beam LL5, and the sixth laser beam LL6 are combined, the color becomes white. The illumination quality of the illumination device 111 is high. The illumination light from the illumination device 110 increases the types of colors that can be identified. The fineness of color identification is improved.

In the embodiment, the full width at half maximum We4 of the fourth laser beam LL4 is, for example, 10 nm or less. More preferably, it is 5 nm or less. The full width at half maximum We5 of the fifth laser beam LL5 is, for example, 10 nm or less. More preferably, it is 5 nm or less. The full width at half maximum We6 of the sixth laser beam LL6 is, for example, 10 nm or less. More preferably, it is 5 nm or less.
By narrowing the full width at half maximum in this way, high brightness can be maintained when the fourth laser beam LL4, the fifth laser beam LL5, and the sixth laser beam LL6 are attenuated by the optical filter.

  The bandwidth of the fourth laser light LL4 is, for example, within 10 nm. More preferably, it is within 5 nm. The bandwidth of the fifth laser beam LL5 is, for example, within 10 nm. More preferably, it is within 5 nm. The bandwidth of the sixth laser beam LL6 is, for example, within 10 nm. More preferably, it is within 5 nm.

  In the embodiment, the absolute value of the difference between the fourth bottom transmission wavelength λt4 and the first bottom transmission wavelength λt1 is, for example, not less than 4 nm and not more than 80 nm. More preferably, it is 6 nm or more and 60 nm or less. The absolute value of the difference between the fifth bottom transmission wavelength λt5 and the second bottom transmission wavelength λt2 is, for example, not less than 4 nm and not more than 80 nm. More preferably, it is 6 nm or more and 60 nm or less. The absolute value of the difference between the sixth bottom transmission wavelength λt6 and the third bottom transmission wavelength λt3 is, for example, not less than 4 nm and not more than 80 nm. More preferably, it is 6 nm or more and 60 nm or less.

  In the embodiment, the full width at half maximum Wt4 of the fourth transmission wavelength region Rt4 is, for example, 10 nm or less. More preferably, it is 5 nm or less. The full width at half maximum Wt5 of the fifth transmission wavelength region Rt5 is, for example, 10 nm or less. More preferably, it is 5 nm or less. The full width at half maximum Wt6 of the sixth transmission wavelength region Rt6 is, for example, 10 nm or less. More preferably, it is 5 nm or less. Thus, since the optical filter 210 is set to have a narrow reflection wavelength region, light loss can be suppressed.

  The laser beam group is, for example, a combination of three laser beams. The wavelengths of the three laser beams are different from each other. In the above, two sets of a laser beam group and an optical filter that attenuates the laser beam group (hereinafter referred to as “a set of a laser beam group and an optical filter”) are provided. The number of sets of laser light groups and optical filters may be three or more.

FIG. 5 is a schematic view illustrating another illumination device according to the embodiment.
As shown in FIG. 5, in the illumination device 112, a light source 50 is further provided in addition to the first laser element 11, the second laser element 12, and the third laser element 13. The light source 50 emits non-coherent light Inc. For example, the total luminous flux amount of the non-coherent light Inc is set to 1/7 or less of the total luminous flux amount of the second laser beam LL2. Thereby, for example, the illumination device 112 can be used as illumination during observation of a celestial body. Light pollution can be suppressed. The non-coherent light Inc is, for example, substantially white.

FIG. 6 is a schematic view illustrating another illumination device according to the embodiment.
As shown in FIG. 6, in the illumination device 113, in addition to the first laser element 11, the second laser element 12, and the third laser element 13, a reflection unit 60 is further provided. The reflection unit 60 has a curved surface 60a on which the first laser beam group is incident. The curved surface 60a of the reflection unit 60 is, for example, a paraboloid or an ellipsoid. The light traveling direction can be controlled in a desired direction by the reflection unit 60. A plurality of laser beams can be easily combined. The first to sixth laser elements 11 to 16 and the reflection unit 60 may be combined.

  A scatterer 68 that scatters laser light may be further provided between the laser element and the reflection unit 60. The scatterer 68 is disposed, for example, at or near the focal point of the reflection unit 60. Thereby, it is easy to synthesize laser beams, and illumination with less unevenness can be obtained.

  In the illumination device 110 to the illumination device 113, an optical fiber may be further provided between the laser element and the scatterer 68. The degree of freedom of spatial arrangement between the scatterer 68 and the laser element in the illumination device is increased.

FIG. 7 is a schematic cross-sectional view illustrating the optical filter according to the embodiment.
As shown in FIG. 7, the first filter element 21 includes a first region 31, a second region 32, and a third region 33.
The second region 32 is aligned with the first region 31 in the first direction D1. The third region 33 is aligned with the first region 31 and the second region 32 in the first direction D1.
The first region 31 includes a plurality of first layers 31a and a plurality of second layers 31b arranged alternately in the first direction D1.
The second region 32 includes a plurality of third layers 32a and a plurality of fourth layers 32b arranged alternately in the first direction D1.
The third region 33 includes a plurality of fifth layers 33a and a plurality of sixth layers 33b arranged alternately in the first direction D1.

The first region 31 is a multilayer film including a plurality of stacked dielectric layers. The refractive index of the first region 31 changes continuously and periodically in the thickness direction. The refractive index is high in the central portion of the first region 31 in the thickness direction, and the refractive index is low in the portion excluding the central portion. The shape of the refractive index distribution in the first region 31 (for example, the envelope shape of the refractive index change) is a spindle shape. In the embodiment, for example, a spindle type rugate structure is used. In the spindle-shaped rugate structure, the refractive index changes continuously and periodically in the thickness direction. In the first region 31, even when the refractive index change is stepped and the refractive index envelope is spindle-shaped, a sufficiently high reflectance and a sufficiently narrow reflectance bandwidth can be obtained.
The second region 32 and the third region 33 are, for example, multilayer films including a plurality of stacked dielectric layers.

(Third embodiment)
FIG. 8 is a schematic view illustrating a lighting system according to the third embodiment.
As shown in FIG. 8, in the illumination system 810 according to the present embodiment, an illumination device 114 and an optical filter 212 are provided.
The illumination device 114 includes a first laser element 11, a second laser element 12, a third laser element 13, a fourth laser element 14, a fifth laser element 15, a sixth laser element 16, and a laser control unit. 38 and the reflection part 60 are included.

  The illumination device 114 is installed, for example, around an astronomical observation facility. In this example, a plurality of lighting devices 114 are installed on the side of the roadway 90 and are used as street lights.

  The optical filter 212 includes a first filter element 21, a second filter element 22, and a filter control unit 39. In this example, either the first filter element 21 or the second filter element 22 is disposed at a predetermined position of the camera light receiving unit 310. The camera light receiving unit 310 is attached to an astronomical telescope (not shown). In response to an instruction from the filter control unit 39, the position control device 48 places the first filter element 21 or the second filter element 22 at a predetermined position of the camera light receiving unit 310. For example, the filter control unit 39 changes the position of the first filter element 21 between the first state and the second state. The filter control unit 39 changes the position of the second filter element 22 between the first state and the second state. The filter control unit 39 may change the position of the camera light receiving unit 310 between the first state and the second state.

  According to this embodiment, the roadway 90 can be illuminated with the illumination device 114. An astronomical object can be observed with the astronomical telescope without being substantially affected by the illumination device 114.

  Of the light emitted by the celestial body to be observed, the light to be observed includes, for example, light having the first peak wavelength λe1, and the illumination device 114 emits the second laser light group. The observer uses the second filter element 22. The lighting device 114 illuminates the roadway 90. The observer can reduce the influence of the lighting device 114.

  Of the light emitted from the celestial body to be observed, for example, when the light to be observed includes light having the fourth peak wavelength λe4, the illumination device 114 emits the first laser light group. The observer uses the first filter element 21. The lighting device 114 illuminates the roadway 90. The observer can reduce the influence of the lighting device 114.

  In the embodiment, for example, the optical filter 210 may be used in combination with a spectacle lens. Light pollution when a user using the visual observation observes a star is reduced.

When the illumination device 113 is used in a range where the distance from a predetermined position (for example, an observation place) is about 100 m, for example, light that is directly incident on the observation device or the eyes is reduced.
When the illumination device 113 is used in a range where the distance from a predetermined position (for example, an observation place) is about 1 km, for example, scattered light from illumination due to buildings, structures, trees, or the like is reduced.

  When the illumination device 113 is used within a range of about 50 km from a predetermined position (for example, an observation place), for example, scattered light due to fine particles in the air is reduced.

  In the embodiment, the lighting device may be used as facility lighting, airport light, or stadium lighting, for example. The lighting device is used as a projector, for example. Since the laser element has high luminance, the boundary of the irradiation area (illumination pattern) becomes clear. It does not substantially irradiate light with an unnecessary wavelength. Light pollution is suppressed.

  In the lighting system, a central control unit may be further provided in addition to the lighting device and the optical filter. The central control unit controls the laser control units of the plurality of illumination devices. On the other hand, for example, the user uses an optical filter corresponding to the laser beam group.

  The embodiments of the present invention have been described above with reference to specific examples. However, the present invention is not limited to these specific examples. For example, regarding the specific configuration of each element such as a laser element, a filter element, a laser control unit, and a filter control unit, those skilled in the art can implement the present invention in the same manner by appropriately selecting from a well-known range, Is included in the scope of the present invention.

  Moreover, what combined any two or more elements of each specific example in the technically possible range is also included in the scope of the present invention as long as the gist of the present invention is included.

  In addition, all lighting devices, optical filters, and lighting systems that can be implemented by those skilled in the art based on the lighting devices, optical filters, and lighting systems described above as embodiments of the present invention are also included in the present invention. As long as the gist is included, it belongs to the scope of the present invention.

  In addition, in the category of the idea of the present invention, those skilled in the art can conceive of various changes and modifications, and it is understood that these changes and modifications also belong to the scope of the present invention. .

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

  DESCRIPTION OF SYMBOLS 11-16 ... 1st-6th laser element, 18 ... Housing | casing, 21 ... 1st filter element, 22 ... 2nd filter element, 28 ... Frame, 31-33 ... 1st-3rd area | region, 31a ... 1st 1 layer 31b 2nd layer 32a 3rd layer 32b 4th layer 33a 5th layer 33b 6th layer 38 laser control unit 39 filter control unit 48 position control device 50 ... Light source 60 ... Reflector 60a ... Curved surface 68 ... Scattering body 90 ... Roadway 110-114 Illuminating device 210-212 Optical filter 310 ... Camera light receiving unit 810 Illuminating system Inc ... Incoherent light, Int1, Int2 ... Intensity, λ ... Wavelength, λe1 to λe6 ... First to sixth peak wavelengths, λt1 to λt6 ... First to sixth bottom transmission wavelengths, λr1 to λr6 ... First to sixth peaks Reflected wave , Ie1 to Ie6 ... first to sixth peak intensities, It1 to It6 ... first to sixth bottom transmittances, Ir1 to Ir6 ... first to sixth peak reflectances, LL1 to LL6 ... first to sixth laser beams Rf ... reflectance, Rt1 to Rt6 ... first to sixth transmission wavelength regions, Rr1 to Rr6 ... first to sixth reflection wavelength regions, Tr ... transmittance, We1 to We6 ... first to sixth full width half maximum, Wt1 ˜Wt6: first to sixth full width at half maximum, Wr1 to Wr6: first to sixth full width at half maximum, D1: first direction

Claims (12)

A first laser element that emits a first laser beam having a first peak wavelength and a full width at half maximum of 5 nanometers or less;
A second laser element that emits a second laser beam having a second peak wavelength that is longer than the first peak wavelength and has a difference from the first peak wavelength of 80 nanometers or more and a full width at half maximum of 5 nanometers or less. When,
A third laser element that emits a third laser beam having a third peak wavelength that is longer than the second peak wavelength and has a difference from the second peak wavelength of 80 nanometers or more and a full width at half maximum of 5 nanometers or less. When,
A lighting device comprising:
A first transmission wavelength region having a first bottom transmission wavelength and a full width at half maximum of 5 nanometers or less;
A second transmission wavelength region having a second bottom transmission wavelength and a full width at half maximum of 5 nanometers or less;
A third transmission wavelength region having a third bottom transmission wavelength and a full width at half maximum of 5 nanometers or less;
An optical filter including a first filter element having:
With
The absolute value of the difference between the first bottom transmission wavelength and the first peak wavelength is 5 nanometers or less,
The absolute value of the difference between the second bottom transmission wavelength and the second peak wavelength is 5 nanometers or less;
The absolute value of the difference between the third bottom transmission wavelength and the third peak wavelength is 5 nanometers or less. The lighting device includes:
A fourth laser element for emitting a fourth laser beam having a fourth peak wavelength having an absolute value of a difference from the first peak wavelength of 6 nanometers or more and 60 nanometers or less and having a full width at half maximum of 5 nanometers or less; ,
A fifth laser element for emitting a fifth laser beam having a fifth peak wavelength having an absolute value of a difference from the second peak wavelength of 6 nanometers or more and 60 nanometers or less and having a full width at half maximum of 5 nanometers or less; ,
A sixth laser element that emits a sixth laser beam having a sixth peak wavelength having an absolute value of a difference from the third peak wavelength of 6 nanometers to 60 nanometers and a full width at half maximum of 5 nanometers or less; ,
Further including
The optical filter is
A fourth transmission wavelength region having a fourth bottom transmission wavelength and a full width at half maximum of 5 nanometers or less;
A fifth transmission wavelength region having a fifth bottom transmission wavelength and a full width at half maximum of 5 nanometers or less;
A sixth transmission wavelength region having a sixth bottom transmission wavelength and a full width at half maximum of 5 nanometers or less;
A second filter element having
The absolute value of the difference between the fourth bottom transmission wavelength and the fourth peak wavelength is 5 nanometers or less;
The absolute value of the difference between the fifth bottom transmission wavelength and the fifth peak wavelength is 5 nanometers or less,
The illumination system according to claim 1, wherein an absolute value of a difference between the sixth bottom transmission wavelength and the sixth peak wavelength is 5 nanometers or less. The illumination device further includes a laser control unit,
The laser controller is
In the first state, the first laser element emits the first laser beam, the second laser element emits the second laser beam, the third laser element emits the third laser beam,
In the second state, the fourth laser element is caused to emit the fourth laser light, the fifth laser element is caused to emit the fifth laser light, and the sixth laser element is caused to emit the sixth laser light. The lighting system according to claim 2. The laser controller is
The intensity of the fourth laser light emitted from the fourth laser element in the first state is lower than the intensity of the fourth laser light emitted from the fourth laser element in the second state; or In the first state, the fourth laser element is not allowed to emit the fourth laser light,
The intensity of the fifth laser light emitted from the fifth laser element in the first state is lower than the intensity of the fifth laser light emitted from the fifth laser element in the second state; or In the first state, the fifth laser element is not allowed to emit the fifth laser light,
The intensity of the sixth laser light emitted from the sixth laser element in the first state is lower than the intensity of the sixth laser light emitted from the sixth laser element in the second state; or In the first state, the sixth laser element does not emit the fifth laser beam,
The intensity of the first laser light emitted from the first laser element in the second state is lower than the intensity of the first laser light emitted from the first laser element in the first state; or In the second state, the first laser element does not emit the first laser beam,
The intensity of the second laser light emitted from the second laser element in the second state is lower than the intensity of the second laser light emitted from the second laser element in the first state; or In the second state, the second laser element does not emit the second laser light,
The intensity of the third laser light emitted from the third laser element in the second state is lower than the intensity of the third laser light emitted from the third laser element in the first state; or The illumination system according to claim 3, wherein in the second state, the third laser light is not emitted from the third laser element. The optical filter further includes a filter control unit,
The illumination system according to claim 3 or 4, wherein the filter control unit changes a position of the first filter element between the first state and the second state. The illumination device further includes a light source that emits non-coherent light,
The illumination system according to claim 1, wherein a total luminous flux amount of the non-coherent light is 1/7 or less of a total luminous flux amount of the second laser light. A first laser element that emits a first laser beam having a first peak wavelength and a full width at half maximum of 5 nanometers or less;
A second laser element that emits a second laser beam having a second peak wavelength that is longer than the first peak wavelength and has a difference from the first peak wavelength of 80 nanometers or more and a full width at half maximum of 5 nanometers or less. When,
A third laser element that emits a third laser beam having a third peak wavelength that is longer than the second peak wavelength and has a difference from the second peak wavelength of 80 nanometers or more and a full width at half maximum of 5 nanometers or less. When,
A lighting device comprising: A fourth laser element for emitting a fourth laser beam having a fourth peak wavelength having an absolute value of a difference from the first peak wavelength of 6 nanometers or more and 60 nanometers or less and having a full width at half maximum of 5 nanometers or less; ,
A fifth laser element for emitting a fifth laser beam having a fifth peak wavelength having an absolute value of a difference from the second peak wavelength of 6 nanometers or more and 60 nanometers or less and having a full width at half maximum of 5 nanometers or less; ,
A sixth laser element that emits a sixth laser beam having a sixth peak wavelength having an absolute value of a difference from the third peak wavelength of 6 nanometers to 60 nanometers and a full width at half maximum of 5 nanometers or less; ,
The lighting device according to claim 7, further comprising: In the first state, the first laser element emits the first laser beam, the second laser element emits the second laser beam, the third laser element emits the third laser beam,
In the second state, the laser that causes the fourth laser element to emit the fourth laser light, causes the fifth laser element to emit the fifth laser light, and causes the sixth laser element to emit the sixth laser light. The lighting device according to claim 8, further comprising a control unit. A first transmission wavelength region having a first bottom transmission wavelength and a full width at half maximum of 5 nanometers or less;
A second transmission wavelength region having a second bottom transmission wavelength and a full width at half maximum of 5 nanometers or less;
A third transmission wavelength region having a third bottom transmission wavelength and a full width at half maximum of 5 nanometers or less;
A first filter element having
The second bottom transmission wavelength is longer than the first bottom transmission wavelength, and the difference between the second bottom transmission wavelength and the first bottom transmission wavelength is 80 nanometers or more,
The third bottom transmission wavelength is longer than the second bottom transmission wavelength, and the difference between the third bottom transmission wavelength and the second bottom transmission wavelength is 80 nanometers or more. A fourth transmission wavelength region having a fourth bottom transmission wavelength and a full width at half maximum of 5 nanometers or less;
A fifth transmission wavelength region having a fifth bottom transmission wavelength and a full width at half maximum of 5 nanometers or less;
A sixth transmission wavelength region having a sixth bottom transmission wavelength and a full width at half maximum of 5 nanometers or less;
A second filter element having
The absolute value of the difference between the fourth bottom transmission wavelength and the first bottom transmission wavelength is 6 nanometers or more and 60 nanometers or less.
The absolute value of the difference between the fifth bottom transmission wavelength and the second bottom transmission wavelength is not less than 6 nanometers and not more than 60 nanometers,
The optical filter according to claim 10, wherein an absolute value of a difference between the sixth bottom transmission wavelength and the third bottom transmission wavelength is 6 nanometers or more and 60 nanometers or less. A filter control unit;
The optical filter according to claim 10 or 11, wherein the filter control unit changes a position of the first filter element between the first state and the second state.

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