Patent Application
20150170549
This invention relates to a fixed-star projection cylinder used in a planetarium or the like.
For projection of all-sky fixed stars in a planetarium, the all sky is divided into a plurality of images and the divided images are projected respectively by a plurality of fixed-star projection cylinders each of which includes a projection template and a projection lens.
On the other hand, the use of an optical fiber to guide light from a light source to a fixed-star projection cylinder is well known (Patent Literatures 1, 2, 3).
Patent Literature 1 discloses a planetarium for projecting an individual fixed-star image onto a screen through a projection lens by emitting light from en end face of an individual optical fiber arranged corresponding to a position of a fixed star.
Patent literature 2 discloses a planetarium having a fixed-star projection cylinder which sends light guided into the fixed-star projection cylinder by an optical fiber to a condenser lens in order to illuminate a projection template perforated for a plurality of fixed-star images, and a high-intensity fixed-star projection cylinder which illuminates a projection template perforated for a single fixed-star image with light guided into the projection cylinder by an optical fiber.
In the known techniques disclosed in the above patent literatures, since all the optical fibers guide light from a shared light source, the color of the fixed stars projected on a screen is single. However, in the case of providing a high-intensity fixed-star projection cylinder such as in the planetarium disclosed by patent Literature 2, by changing the color of the light source of the optical fiber guiding the light into the high-intensity fixed-star projection cylinder, only a high-visibility, bright star is represented in the color of the fixed star. On the other hand, in the fixed-star projection cylinder which sending the light guided into the fixed-star projection cylinder by the optical fiber to the condenser lens to illuminates the projection template perforated for a plurality of fixed-star images, the color of the fixed star projected on the screen is unavoidably single.
Next, Patent Literature 3 discloses a planetarium in which an optical fiber plate which is an optical member including a bundle of optical fibers is placed such that the light exit side of the optical fiber plate faces a projection lens, a transmissive liquid crystal panel and an imaging lens are placed between a light source and an input end face of the optical fiber plate, and light passing through a pixel of the transmissive LC panel in a fixed star image generated on the transmissive LC panel is allowed to enter only one optical fiber.
Patent Literature 1: JP-A No. S62-191818
As described above, in typical planetariums, only a high-visibility, bright star is represented by use of a color of the star. This is because the structure of the fixed-star cylinder makes it difficult to reproduce individual star colors for 10,000 stars which are observable with the naked eye.
Therefore, a starlit sky made out of fixed stars with various colors responsive to color temperatures of the respective fixed stars is projected by merely coloring only high-visibility, bright stars, thus differing considerably from the situation of zeal starlit sky.
The present invention has been made in light of the aforementioned disadvantage in the related art, and accordingly an object of the present invention is to provide a fixed-star projection cylinder capable of reproducing a color unique to each fixed star for reproduction of situation of real starlit sky, although only a color unique to a specific bright fixed star is reproduced in the related art.
In a fixed-star projection cylinder according to the present invention, luminous fluxes having a plurality of color temperatures or color tones matched to color temperatures of individual fixed stars to be projected are generated. Since such a luminous flux is typically diffused light, the lights having the colors are mixed up before they reach a projection lens, making it impossible to add an individual color or color tone to each fixed star. To avoid this, light guiding means such as an optical fiber or the like is used to guide light of an individual color directly to a position of a fixed star having a corresponding spectral type on the fixed-star template or a position in which a corresponding fixed star should be located. This makes it possible to add light of an appropriate color to the fixed star.
In other words, a difference between the fixed-star projection cylinder according to the present invention and the fixed-star projection cylinders in the related art is that individual light guiding means is provided for each individual fixed star to be projected, and the light emitted from the light guiding means is designed to have a color based on the spectral type of the fixed star to be projected.
The fixed-star projection cylinder for a planetarium described in claim 1 is to project individual fixed-star images onto a screen through a projection lens by either light traveling from exit end faces of individual light guiding means to pass through individual light transmissive portions of a fixed-star projection template arranged corresponding to positions of fixed stars or light traveling from exit end faces of individual light guiding means arranged corresponding to positions of fixed stars. In the fixed-star projection cylinder, a spectral type is defined for each individual fixed-star image to be projected. A plurality of types of light differing in either color temperature or color tone are emitted from the exit end faces of the individual light guiding means for reproduction of colors based on the defined spectral types in projection.
Further, the fixed-star projection cylinder described in claim 2 has a feature that, in the aforementioned fixed-star projection cylinder, optical fibers are used as the light guiding means.
Further, the fixed-star projection cylinder described in claim 3 has a feature that, in the aforementioned fixed-star projection cylinder, means is designed to guide lights emitted from a plurality of light sources with either different color temperatures or different color tones from the entry end faces of the individual light guiding means to emit a plurality of types of light with either different color temperatures or different color tones from the exit end faces of the individual light guiding means.
Further, the fixed-star projection cylinder described in claim 4 has a feature that, in the aforementioned fixed-star projection cylinder, a plurality of the light sources with either different color temperatures or different color tones are placed in the fixed-star projection cylinder.
Further, the fixed-star projection cylinder described in claim 5 has a feature that, in the aforementioned fixed-star projection cylinder, a plurality of the light sources with either different color temperatures or different color tones are placed outside the fixed-star projection cylinder.
Further, the fixed-star projection cylinder described in claim 6 has a feature that, in the aforementioned fixed-star projection cylinder, a single light source is shared among a plurality of the light guiding means assigned to the same color temperature or color tone of light to be emitted in either the same fixed-star projection cylinder or a different fixed-star projection cylinder.
Further, the fixed-star projection cylinder described in claim 7 has a feature that, in the aforementioned fixed-star projection cylinder, a plurality of luminous fluxes of either different color temperatures or different color tones are generated by combined colors of a plurality of different emission colors of the light sources.
Further, the fixed-star projection cylinder described in claim 8 has a feature that, in the aforementioned fixed-star projection cylinder, the fixed-star projection cylinder is capable of individually varying luminance intensities of a plurality of the light sources for creation of the combined colors.
Further, the fixed-star projection cylinder described in claim 9 has a feature that, in the aforementioned fixed-star projection cylinder, a filter for either passage or attenuation of light of a specific wavelength is placed between a light source and the entry end face of the light guiding means to serve as means for emitting a plurality of the types of light differing in either color temperature or color tone from the exit end faces of the individual light guiding means.
Further, the fixed-star projection cylinder described in claim 10 has a feature that, in the aforementioned fixed-star projection cylinder, a transmissive color liquid crystal panel is used as a filter for either passage or attenuation of light of a specific wavelength by controlling sets of nearby pixels on the transmissive color liquid crystal panel, each set of nearby pixels being assigned to a color.
Further, the fixed-star projection cylinder described in claim 11 has a feature that, in the aforementioned fixed-star projection cylinder, the fixed-star projection cylinder is capable of controlling transmittance of the sets of nearby pixels on the transmissive color liquid crystal panel as required.
Unlike the fixed-star projection cylinders in the related art, in a starlit sky reproduced by the fixed-star projection cylinder according to the present invention configured as described above, suitable colors corresponding to spectral types of fixed stars are added to all the fixed stars, making it possible to reproduce the same starlit sky as real night sky.
In this case, with the fixed-star projection cylinder described in claim 6, a light source is shared among a plurality of the light guiding means assigned to the same color temperature or color tone of light to be emitted in either the same fixed-star projection cylinder or a different fixed-star projection cylinder. Because of this, a reduction in the number of light sources can be achieved, eliminating a disadvantageous problem of occupying space in the fixed-star projection cylinder or the planetarium apparatus and a disadvantageous problem of extremely heat generation.
Also, with the fixed-star projection cylinder described in claim 9, since a filter for either passage or attenuation of light of a specific wavelength is placed between a light source and the entry end face of the light guiding means to serve as means for emitting a plurality of the types of light differing in either color temperature or color tone from the exit end faces of the individual light guiding means, the light source itself is for a single color, making it possible to further reduce the number of light sources.
Concrete exemplary embodiments of a fixed-star projection cylinder according to the present invention will be descried below with reference to the accompanying drawings.
Here, 5 classes shown below is an example of the number of classes of colors of the fixed star images.
In the embodiment, means is designed to guide lights emitted from a plurality of light sources with different color temperatures or color tones from the entry end faces of the individual light guiding means to emit a plurality of types of light with different color temperatures or color tones from the exit end faces of the individual light guiding means, and a plurality of light sources 5 adapted to the spectral types of the fixed stars are used.
In
In this case, the shared use of a single light source 5 among a plurality of optical fibers 9 assigned to the same color temperature or color tone of light to be emitted reduces the number of light sources.
A plurality of luminous fluxes of different color temperatures or color tones may be generated by combined colors of a plurality of different emission colors of light sources, which is not shown.
In
In this embodiment, as in the case of the first embodiment, a single light source 15 is shared among a plurality of the optical fibers 14 assigned to the same color temperature or color tone of light to be emitted. The common use in the projection cylinder is possible 4. Also, since the light sources are placed outside the projection cylinder, a single light source can be shared among a plurality of projection cylinders. In
As a result, in the embodiment a reduction in the number of types of the light sources can be achieved.
As described in the embodiment, the use of the transmissive color liquid crystal panel to provide different colors makes it possible to adjustably vary the color and the intensity as well as to significantly increase the number of representable colors. In addition, reproduction of a variable star and/or of changes in color and/or brightness made by stellar evolution is made possible.
In the aforementioned embodiments, individual fixed-star images are projected onto a screen through a projection lens by light traveling from individual exit end faces of light guiding means to pass through individual light transmissive portions of a fixed-star projection template arranged corresponding to positions of fixed stars. In another way, individual fixed-star images may be projected onto a screen through a projection lens by light traveling from individual exit end faces of light guiding means arranged corresponding to estimated positions of fixed stars.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2013-248773 | Nov 2013 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2014/052816 | 1/31/2014 | WO | 00 |
