Illuminating device comprising a pump radiation source

1. An illuminating device comprising:

a pump radiation source for emitting pump radiation as a beam bundle,

a phosphor element for converting the pump radiation into conversion light, and

a lens system between the pump radiation source and the phosphor element,

which is penetrated by the pump beam bundle,

wherein the lens system has a focus and the phosphor element is arranged at the focus,

wherein a lens of the lens system has a scattering means which scattering means the pump beam bundle penetrates and is widened at the same time, so that the pump beam bundle is incident on the phosphor element in a manner widened around a focus point;

wherein the lens comprising the scattering means has a spherical light entry surface; and

wherein the pump beam bundle is incident on a pump radiation incidence surface of the phosphor element, which has a mean extension x, and a sphere on which the spherical light entry surface is based has a radius R, wherein R≥x/2.

2. The illuminating device as claimed in claim 1 , wherein the scattering means widens the opening angle of the pump beam bundle by at least 0.5° and at most 10°.

3. The illuminating device as claimed in claim 1 , wherein the scattering means is provided at a light entry surface of the lens.

4. The illuminating device as claimed in claim 1 , wherein the pump beam bundle is incident on a pump radiation incidence surface of the phosphor element and a surface focal point of the pump radiation incidence surface has a distance d taken along a surface normal in relation to the spherical light entry surface and a sphere on which the spherical light entry surface is based has a radius R, wherein d≥0.9·R, preferably d=R.

5. The illuminating device as claimed in claim 1 , wherein the lens is a planar-spherical lens, and wherein the phosphor element is arranged at alight exit surface of the lens.

6. The illuminating device as claimed in claim 1 , wherein a sphere on which the spherical light entry surface is based has a center point and the pump beam bundle is incident on the spherical light entry surface convergently in relation to the center point.

7. The illuminating device as claimed in claim 5 , wherein the lens has an optical axis, which is perpendicular to the light exit surface, wherein Θ c is the critical angle for total reflection at the light exit surface, and wherein the pump beam bundle penetrates the spherical light entry surface with a focal point direction which is tilted by an angle Θ≥Θ c in relation to the optical axis.

8. The illuminating device as claimed in claim 1 , further comprising a plurality of pump radiation sources.

9. The illuminating device as claimed in claim 7 , wherein a first pump beam bundle, which originates from a first pump radiation source, and a second pump beam bundle, which originates from a second pump radiation source, are rotationally symmetrical in relation to one another in the planar-spherical lens with respect to the optical axis, specifically precisely in a twofold manner having an angle of rotation of 180°.

10. The illuminating device as claimed in claim 1 , wherein the light entry surface of the lens is at least regionally provided with a reflection layer.

11. The illuminating device as claimed in claim 10 , wherein the reflection layer is reflective both for the conversion light and for the pump radiation, wherein a region of the light entry surface, which the pump beam bundle penetrates, is free of the reflection layer.

12. The illuminating device as claimed in claim 3 , wherein the scattering means is provided at the light entry surface of the lens as a coating or surface roughening.

13. The illuminating device as claimed in claim 5 , wherein the light exit surface of the lens, which is opposite to the spherical light entry surface, is planar.

14. A use of an illuminating device comprising:

emitting pump radiation as a beam bundle with a pump radiation source,

converting the pump radiation into conversion light with a phosphor element, and penetrating a lens system between the pump radiation source and the phosphor element with the pump beam bundle,

wherein the lens system has a focus and the phosphor element is arranged at the focus,

wherein a lens of the lens system has a scattering means which scattering means the pump beam bundle penetrates and is widened at the same time, so that the pump beam bundle is incident on the phosphor element in a manner widened around a focus point;

wherein the lens comprising the scattering means has a spherical light entry surface;

wherein the pump beam bundle is incident on a pump radiation incidence surface of the phosphor element, which has a mean extension x, and a sphere on which the spherical light entry surface is based has a radius R, wherein R≥x/2.

15. An illuminating device comprising:

a pump radiation source for emitting pump radiation as a beam bundle,

a phosphor element for converting the pump radiation into conversion light, and

a lens system between the pump radiation source and the phosphor element,

which is penetrated by the pump beam bundle,

wherein the lens system has a focus and the phosphor element is arranged at the focus,

wherein a lens of the lens system has a scattering means which scattering means the pump beam bundle penetrates and is widened at the same time, so that the pump beam bundle is incident on the phosphor element in a manner widened around a focus point;

wherein the lens comprising the scattering means has a spherical light entry surface; and

wherein the pump beam bundle is incident on a pump radiation incidence surface of the phosphor element and a surface focal point of the pump radiation incidence surface has a distance d taken along a surface normal in relation to the spherical light entry surface and a sphere on which the spherical light entry surface is based has a radius R, wherein d≥0.9·R, preferably d=R.