Camera

1. A camera for taking an image possessing:

an image-pickup portion which takes an image of a subject;

a hydrophilic filter which is formed so that a hydrophilic surface is exposed on an outer surface of said camera, and which transmits a light entering from the subject to said image-pickup portion; and

a ultraviolet light generating portion, which irradiates an ultraviolet light to the surface of the external surface of said camera on said hydrophilic filter from the edge portion of said hydrophilic filter; and

said hydrophilic filter comprising a photocatalytic substance which decomposes organic substances adhered thereon due to the ultraviolet light.

2. The camera according to claim 1 , wherein said ultraviolet light generating portion possesses a light emitting diode.

3. The camera according to claim 2 , wherein said ultraviolet light generating portion further possesses a reflecting mirror provided along at least edge portion of said hydrophilic filter, and

wherein said reflecting mirror reflects the ultraviolet light from said light emitting diode to irradiate the ultraviolet light to said hydrophilic filter.

4. The camera according to claim 3 , wherein said ultraviolet light generating portion further possesses an external circumferential member made of a transparent material provided at least along the edge portion of said hydrophilic filter,

said reflecting mirror irradiates the ultraviolet light to said hydrophilic filter via said external circumferential member, and

said portion exposed of the surface of external circumferential member on the edge portion of said hydrophilic filter at the outer surface is made hydrophilic.

5. The camera according to claim 2 , wherein said light emitting diode comprises a mold portion at least partially exposed on the edge portion of said hydrophilic filter, and

said portion of the surface of the mold portion exposed to the edge portion of said hydrophilic filter is made hydrophilic.

6. A vehicle rear side camera comprising the camera according to claim 1 , mounted so that said hydrophilic filter is directed downward.

7. A camera for taking an image possessing:

a image-pickup portion which takes an image of a subject;

a hydrophilic filter which is formed so that a hydrophilic surface is exposed on an outer surface of said camera, and which transmits a light entering from the subject to said image-pickup portion;

a cover for covering said hydrophilic filter from the external surface side of said camera, when said image-pickup portion does not take an image, and

a ultraviolet light generating portion which is provided at a surface facing said hydrophilic filter of said cover, and which irradiates a ultraviolet light towards the external surface side of said camera when said cover covers said hydrophilic filter; and

said hydrophilic filter comprising a photocatalytic substance decomposing organic substances adhered thereon due to the ultraviolet light.

8. The camera according to claim 7 , which is provided on a vehicle, and

wherein said cover covers said hydrophilic filter upon stopping the engine of said vehicle, and

said ultraviolet light generating portion generates a ultraviolet light for a prescribed period of time upon covering the said hydrophilic filter with said cover.

9. A vehicle rear side camera comprising the camera according to claim 7 mounted so that said hydrophilic filter is directed downward.

10. The camera according to claim 1 or 7 , wherein said hydrophilic filter is formed on a substrate, which is one of a transparent substrate or lens for said camera,

said substrate is made of a material having a refracting ratio smaller than the layer comprising a photocatalytic substance of said hydrophilic filter, and

said hydrophilic filter further possesses an intermediate layer having a refracting ratio between a layer comprising a photocatalytic substance and said substrate formed between a layer comprising a photocatalytic substance and said substrate.

11. The camera according to claim 1 or 7 , further comprising a filter for cutting an ultraviolet between the hydrophilic filter and the image-pickup portion.

12. The camera according to claim 1 or 7 , wherein said ultraviolet light generating portion irradiates the ultraviolet over the entire portions of the hydrophilic filter in a uniform manner.

13. The camera according to claim 1 or 7 , wherein said ultraviolet light generating portion possesses a filter for cutting visible lights.

14. The camera according to claim 1 or 7 , wherein said ultraviolet light generating portion possesses a light-guide plate.