Illumination device

1. An illumination device comprising:

a light source configured to generate primary light having a Gaussian intensity distribution;

an intensity-distribution converting member configured to convert the primary light to generate secondary light having a top-hat type intensity distribution;

a wavelength converter configured to receive the secondary light from a light-receiving surface, generate tertiary light including the secondary light and wavelength-converted light in which a wavelength of said secondary light has been converted, and emit the tertiary light from an emission surface; and

an antenna array having a plurality of optical antennas formed on said emission surface of said wavelength converter and arranged at a period larger than an optical wavelength of the secondary light in said wavelength converter,

wherein:

said light-receiving surface of said wavelength converter has an irradiated region irradiated with the secondary light and a peripheral region provided around said irradiated region,

said emission surface of said wavelength converter has a first emission region corresponding to said irradiated region and a second emission region corresponding to said peripheral region, and

said antenna array includes a first sub-array comprising a plurality of optical antennas arranged on said first emission region of said emission surface, and a second sub-array comprising a plurality of optical antennas arranged on said second emission region and having a larger antenna occupancy ratio per unit area than that of said first sub-array.

2. An illumination device comprising:

a light source configured to generate primary light having a Gaussian intensity distribution;

an intensity-distribution converting member configured to convert the primary light to generate secondary light having a top-hat type intensity distribution;

a wavelength converter configured to receive the secondary light from a light-receiving surface, generate tertiary light including the secondary light and wavelength-converted light in which a wavelength of said secondary light has been converted, and emit the tertiary light from an emission surface; and

an antenna array having a plurality of optical antennas formed on said emission surface of said wavelength converter and arranged at a period larger than an optical wavelength of the secondary light in said wavelength converter,

wherein:

said antenna array is arranged in a square lattice pattern on said emission surface,

said light-receiving surface of said wavelength converter has an irradiated region irradiated with the secondary light and a peripheral region provided around said irradiated region, and

said wavelength converter has a recessed portion provided rotationally symmetrically with respect to an optical axis of the secondary light in said irradiated region of said light-receiving surface.

3. An illumination device comprising:

a light source configured to generate primary light having a Gaussian intensity distribution;

an intensity-distribution converting member configured to convert the primary light to generate secondary light having a top-hat type intensity distribution;

a wavelength converter configured to receive the secondary light from a light-receiving surface, generate tertiary light including the secondary light and wavelength-converted light in which a wavelength of said secondary light has been converted, and emit the tertiary light from an emission surface; and

an antenna array having a plurality of optical antennas formed on said emission surface of said wavelength converter and arranged at a period larger than an optical wavelength of the secondary light in said wavelength converter,

wherein:

said antenna array is arranged in a hexagonal lattice pattern on said emission surface,

said light-receiving surface of said wavelength converter has an irradiated region irradiated with the secondary light and a peripheral region provided around said irradiated region, and

said wavelength converter has a projected portion provided rotationally symmetrically with respect to an optical axis of the secondary light in said irradiated region of said light-receiving surface.

4. The illumination device according to claim 1 , wherein said intensity-distribution converting member comprises a beam homogenizer.

5. The illumination device according to claim 2 , wherein said intensity-distribution converting member comprises a beam homogenizer.

6. The illumination device according to claim 3 , wherein said intensity-distribution converting member comprises a beam homogenizer.

7. The illumination device according to claim 1 , wherein said light source is a laser light source configured to generate laser light as the primary light.

8. The illumination device according to claim 2 , wherein said light source is a laser light source configured to generate laser light as the primary light.

9. The illumination device according to claim 3 , wherein said light source is a laser light source configured to generate laser light as the primary light.

10. The illumination device according to claim 4 , wherein said light source is a laser light source configured to generate laser light as the primary light.

11. The illumination device according to claim 5 , wherein said light source is a laser light source configured to generate laser light as the primary light.

12. The illumination device according to claim 6 , wherein said light source is a laser light source configured to generate laser light as the primary light.

13. The illumination device according to claim 1 , wherein each of the plurality of antennas is made of metal with a columnar or conical shape.

14. The illumination device according to claim 2 , wherein each of the plurality of antennas is made of metal with a columnar or conical shape.