1. A semiconductor laser element comprising:
a semiconductor element layer including an active layer and having an emitting side cavity facet and a reflecting side cavity facet; and
a facet coating film on a surface of said emitting side cavity facet, wherein
said facet coating film includes a photocatalytic layer arranged on an outermost surface of said facet coating film and a dielectric layer arranged between said photocatalytic layer and said emitting side cavity facet, and
a thickness of said dielectric layer is set to a thickness defined by m\xd7\u03bb(2\xd7n) (m is an integer), where a wavelength of a laser beam emitted from said active layer is \u03bb and a refractive index of said dielectric layer is n, and at least 1 \u03bcm.
2. The semiconductor laser element according to claim 1, wherein
a thickness of said photocatalytic layer is smaller than said thickness of said dielectric layer.
3. The semiconductor laser element according to claim 2, wherein
said photocatalytic layer is set to a thickness defined by m\xd7\u03bb(2\xd7n) (m is an integer).
4. The semiconductor laser element according to claim 2, wherein
a refractive index of said photocatalytic layer is larger than said refractive index of said dielectric layer.
5. The semiconductor laser element according to claim 1, wherein
said photocatalytic layer includes a microcrystalline layer of TiO2 and an amorphous layer of TiO2.
6. The semiconductor laser element according to claim 5, wherein
said photocatalytic layer further includes a layer having a crystalline substance of TiO2, formed in a portion corresponding to said active layer.
7. The semiconductor laser element according to claim 1, wherein
said photocatalytic layer and said dielectric layer are in contact with each other.
8. The semiconductor laser element according to claim 1, wherein
said photocatalytic layer is formed on said dielectric layer through a first nitride film.
9. The semiconductor laser element according to claim 1, wherein
said dielectric layer is made of a SiO2 film.
10. The semiconductor laser element according to claim 1, wherein
said dielectric layer has a multi-layer film structure made of a plurality of dielectric films, and
a thickness of each of said plurality of dielectric films is set to a thickness defined by m\xd7\u03bb(2\xd7n) (m is an integer), where said wavelength of said laser beam emitted from said active layer is \u03bb and a refractive index of each of said plurality of dielectric films is n, while said thickness of said dielectric layer is at least 1 \u03bcm.
11. The semiconductor laser element according to claim 10, wherein
said dielectric layer has said multi-layer film structure obtained by stacking a first dielectric film of SiO2 and a second dielectric film of AlON, and
a thickness of said first dielectric film is larger than a thickness of said second dielectric film.
12. The semiconductor laser element according to claim 11, wherein
at least two said first dielectric films and at least two said second dielectric films are alternately stacked in said dielectric layer.
13. The semiconductor laser element according to claim 1, wherein
said facet coating film further includes a reflectance control layer controlling a reflectance of said emitting side cavity facet.
14. The semiconductor laser element according to claim 13, wherein
a high refractive index layer having a refractive index larger than said refractive index of said dielectric layer and a low refractive index layer having a refractive index smaller than said refractive index of said high refractive index layer are stacked in said reflectance control layer, and
said dielectric layer and said reflectance control layer are arranged through said high refractive index layer of said reflectance control layer.
15. The semiconductor laser element according to claim 1, wherein
said facet coating film further includes an oxidation preventing layer preventing oxidation of said emitting side cavity facet.
16. The semiconductor laser element according to claim 15, wherein
said oxidation preventing layer is a dielectric film made of a plurality of layers.
17. The semiconductor laser element according to claim 15, wherein
said oxidation preventing layer has a second nitride film coming into contact with said emitting side cavity facet.
18. The semiconductor laser element according to claim 1, wherein
said semiconductor element layer is made of a nitride-based semiconductor.
19. A semiconductor laser device comprising:
a semiconductor laser element including a semiconductor element layer including an active layer and having an emitting side cavity facet and a reflecting side cavity facet, and a facet coating film on a surface of said emitting side cavity facet; and
an open-to-atmosphere-type package mounting with said semiconductor laser element, wherein
said facet coating film includes a photocatalytic layer arranged on an outermost surface of said facet coating film and a dielectric layer arranged between said photocatalytic layer and said emitting side cavity facet, and
a thickness of said dielectric layer is set to a thickness defined by m\xd7\u03bb(2\xd7n) (m is an integer), where a wavelength of a laser beam emitted from said active layer is \u03bb and a refractive index of said dielectric layer is n, and at least 1 \u03bcm.
20. An optical apparatus comprising:
a semiconductor laser device including a semiconductor laser element having a semiconductor element layer including an active layer and having an emitting side cavity facet and a reflecting side cavity facet, and a facet coating film on a surface of said emitting side cavity facet, and an open-to-atmosphere-type package mounting with said semiconductor laser element; and
an optical system controlling a beam emitted from said semiconductor laser element, wherein
said facet coating film includes a photocatalytic layer arranged on an outermost surface of said facet coating film and a dielectric layer arranged between said photocatalytic layer and said emitting side cavity facet, and
a thickness of said dielectric layer is set to a thickness defined by m\xd7\u03bb(2\xd7n) (m is an integer), where a wavelength of a laser beam emitted from said active layer is \u03bb and a refractive index of said dielectric layer is n, and at least 1 \u03bcm.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A decoding apparatus which decodes compressed data that represents an image signal composed of a plurality of components as a compressed code by making the resolutions of the individual components differ from one another, the decoding apparatus comprising:
an input section which decodes compressed data and takes in the individual components independently;
a reduction circuit which reduces and changes a size corresponding to the processing unit and resolution of any one of the components, and reduces the size according to the lowest resolution of said plurality of components; and
a conversion section which converts into a decoded image signal in a specific format by using reduced components and uncompressed components.
2. The decoding apparatus according to claim 1, wherein said plurality of components include main and sub components, and
the reduction circuit performs decoding in such a manner that the resolutions of the main and sub components are made equal to the lowest resolution of the components.
3. The decoding apparatus according to claim 1, wherein the conversion section further includes a circuit which decodes a signal with the highest resolution of the components.
4. The decoding apparatus according to claim 1, further comprising a plurality of decoded image processing sections corresponding to the number of the components and the resolutions of the respective components.
5. A decoding method which decodes compressed data that represents an image signal composed of a plurality of components as a compressed code by making the resolutions of the individual components differ from one another, the decoding method comprising:
taking in independently from an input section the individual components obtained by decoding the compressed data;
causing a reduction circuit to reduce and change a size corresponding to the processing unit and resolution of any one of the components, and to reduce the size according to the lowest resolution of said plurality of components; and
causing a conversion section to convert into a decoded image signal in a specific format by using reduced components and uncompressed components.
6. The decoding method according to claim 5, wherein said plurality of components include main and sub components, and
the reduction circuit performs decoding in such a manner that the resolutions of the main and sub components are made equal to the lowest resolution of the components.
7. The decoding method according to claim 5, wherein the conversion section further decodes a signal with the highest resolution of the components.
8. The decoding method according to claim 5, further obtaining a decoded output according to the number of the components and the resolutions of the respective components.
9. A decoding apparatus which decodes compressed data that represents an image signal composed of a plurality of components as a compressed code by making the resolutions of the individual components differ from one another, the decoding apparatus comprising:
input means which decodes compressed data and takes in the individual components independently;
reduction means which reduces and changes a size corresponding to the processing unit and resolution of any one of the components, and reduces the size according to the lowest resolution of said plurality of components; and
conversion means which converts into a decoded image signal in a specific format by using reduced components and uncompressed components.