Fluorescent substrate and method for producing the same, and display device

1. A fluorescent substrate comprising:

a fluorescent layer which emits light by receiving excitation light; and

a reflecting film being provided both (i) on a side surface(s) of the fluorescent layer and (ii) on a surface of the fluorescent layer, on which surface the excitation light is incident, the reflecting film (I) transmitting a component having a peak wavelength of the excitation light, and (II) reflecting a component having a peak wavelength of the light emitted from the fluorescent layer, the reflecting film containing at least gold.

2. The fluorescent substrate as set forth in claim 1 , wherein:

the reflecting film (i) transmits 80% or more of the component having the peak wavelength of the excitation light and (ii) reflects 80% or more of the component having the peak wavelength of the light emitted from the fluorescent layer.

3. The fluorescent substrate as set forth in claim 2 , wherein:

the reflecting film (i) transmits 90% or more of the component having the peak wavelength of the excitation light and (ii) reflects 90% or more of the component having the peak wavelength of the light emitted from the fluorescent layer.

4. The fluorescent substrate as set forth in claim 1 , wherein:

an excitation light incident side of the reflecting film serves as a front side;

a light-extraction side of the fluorescent substrate serves as a backside; and

a maximum film thickness of the reflecting film on the side surface(s) of the fluorescent layer is greater than a maximum film thickness of the reflecting film on the front side.

5. The fluorescent substrate as set forth in claim 1 , wherein:

a film thickness of the reflecting film containing at least gold is in a range of 10 nm to 40 nm.

6. The fluorescent substrate as set forth in claim 1 , wherein:

the fluorescent layer is made from an inorganic fluorescent material.

7. The fluorescent substrate as set forth in claim 1 , wherein:

the fluorescent layer is constituted by a plurality of sorts of fluorescent layer provided on the fluorescent substrate, which plurality of sorts of fluorescent layer are made from different fluorescent materials, respectively; and

a light-absorbing layer is provided in each space between adjacent ones of the plurality of sorts of fluorescent layer.

8. The fluorescent substrate as set forth in claim 1 , wherein:

the fluorescent layer is formed to have a tapered shape.

9. The fluorescent substrate as set forth in claim 4 , wherein:

the reflecting film is such that a film thickness of the reflecting film is reduced as being closer to the front side.

10. A display device comprising:

a fluorescent substrate recited in claim 1 ; and

a light source for emitting, toward the fluorescent substrate, excitation light which (i) has a peak wavelength in a range from an ultraviolet region to a blue-color region and (ii) excites the fluorescent layer.

11. The display device as set forth in claim 10 , wherein:

the light source includes an organic electroluminescence element, an inorganic electroluminescence element, or a light-emitting diode.

12. The display device as set forth in claim 11 , wherein:

the light source is driven by an active element.

13. The display device as set forth in claim 12 , wherein:

the light emitted from the fluorescent layer is emitted from a substrate which is provided to face another substrate on which the active element is provided.

14. The display device as set forth in claim 10 , further comprising:

a liquid crystal element provided between the fluorescent substrate and the light source, the liquid crystal element being subjected to switching by receiving a voltage.

15. A method of manufacturing a fluorescent substrate, the method comprising the steps of:

(a) providing a fluorescent layer on a substrate, the fluorescent layer emitting light by receiving excitation light; and

(b) providing a film both (i) on a side surface(s) of the fluorescent layer and (ii) on a surface of the fluorescent layer, on which surface the excitation light is incident, the film (I) transmitting a component having a peak wavelength of the excitation light and (II) reflecting a component having a peak wavelength of the light emitted from the fluorescent layer, the reflecting film containing at least gold.

16. The method as set forth in claim 15 , wherein:

in said step (a), the fluorescent layer is provided by a screen printing method, an ink jet method, or a nozzle coat method.