Fresnel lens spotlight with coupled variation of the spacing of lighting elements

1 . A Fresnel lens spotlight having an emitted light beam with an adjustable aperture angle, comprising:

a reflector,

a lamp; and

at least one Fresnel lens having a negative focal length that defines a virtual focal point.

2 . The Fresnel lens spotlight as claimed in claim 1 , wherein the reflector has a reflector focal point that is remote from the reflector so that the reflector focal point can be superimposed on the virtual focal point in the spot position of the Fresnel lens spotlight.

3 . The Fresnel lens spotlight as claimed in claim 1 , wherein the at least one Fresnel lens is a biconcave negative lens.

4 . The Fresnel lens spotlight as claimed in claim 1 , wherein the at least one Fresnel lens comprises a double lens with chromatically corrected imaging characteristics.

5 . The Fresnel lens spotlight as claimed in claim 1 , wherein the at least one Fresnel lens comprises an integrated diffusing glass.

6 . The Fresnel lens spotlight as claimed in claim 5 , wherein the integrated diffusing glass is circular and is arranged at the center of the at least one Fresnel lens.

7 . A Fresnel lens spotlight having an emitted light beam with an adjustable aperture angle, comprising:

a reflector;

a lamp;

a Fresnel lens having a negative focal length that defines a virtual focal point; and

a first distance being defined between the Fresnel lens and the reflector, said first distance being variable in a defined geometric relationship with respect to a second distance defined between the lamp and the reflector on the basis of the adjustable aperture angle to be for the emitted light beam.

8 . The Fresnel lens spotlight as claimed in claim 7 , wherein the second distance can be adjusted by arranging the lamp so that it can be moved with respect to an apex of the reflector.

9 . The Fresnel lens spotlight as claimed in claim 7 , wherein the reflector comprises a metallic or transparent dielectric glass and/or plastic.

10 . The Fresnel lens spotlight as claimed in claim 7 , wherein the reflector comprises at least one surface having a system of optically thin layers.

11 . The Fresnel lens spotlight as claimed claim 7 , wherein the reflector comprises a surface coated with aluminum.

12 . The Fresnel lens spotlight as claimed in claim 7 , wherein the reflector is structured to scatter light and/or the at least one Fresnel lens is structured to scatter light.

13 . (canceled)

14 . The Fresnel lens spotlight as claimed in claim 7 , wherein the reflector and/or the at least one Fresnel lens are/is coated on at least one side.

15 . The Fresnel lens spotlight as claimed in claim 14 , wherein the coating on the at least one Fresnel lens is a dielectric interference layer system that changes the spectrum of the light passing through it.

16 . The Fresnel lens spotlight as claimed in claim 7 , wherein the lamp is selected from the group consisting of a halogen lamp, a light-emitting diode, a light-emitting diode array, and a gas discharge lamp.

17 . The Fresnel lens spotlight as claimed in claim 7 , further comprising an auxiliary reflector arranged between the at least one Fresnel lens and the reflector.

18 . The Fresnel lens spotlight as claimed in claim 7 , wherein the at least one Fresnel lens is thermally prestressed, on its surface.

19 . A lighting set having an emitted light beam with an adjustable aperture angle, comprising:

a reflector;

a lamp;

a Fresnel lens having a negative focal length that defines a virtual focal point;

a first distance being defined between the Fresnel lens and the reflector, said first distance being variable in a defined geometric relationship with respect to a second distance defined between the lamp and the reflector on the basis of the adjustable aperture angle for the emitted light beam; and

an associated electrical power supply unit or ballast.

20 . (canceled)

21 . A flashlight having an emitted light beam with an adjustable aperture angle, comprising:

a reflector;

a lamp;

a Fresnel lens having a negative focal length that defines a virtual focal point;

a first distance being defined between the Fresnel lens and the reflector, said first distance being variable in a defined geometric relationship with respect to a second distance defined between the lamp and the reflector on the basis of the adjustable aperture angle for the emitted light beam; and

an electrical energy source.

22 . The Fresnel lens spotlight as claimed in claim 7 , wherein the reflector has a reflector focal point that is remote from the reflector so that the reflector focal point can be superimposed on the virtual focal point in the spot position of the Fresnel lens spotlight.

23 . The Fresnel lens spotlight as claimed in claim 7 , wherein the Fresnel lens is a biconcave negative lens.

24 . The Fresnel lens spotlight as claimed in claim 7 , wherein the Fresnel lens comprises a double lens with chromatically corrected imaging characteristics.

25 . The Fresnel lens spotlight as claimed in claim 7 , wherein the Fresnel lens comprises an integrated diffusing glass.

26 . The Fresnel lens spotlight as claimed in claim 25 , wherein the integrated diffusing glass is circular and is arranged at the center of the Fresnel lens.

27 . The Fresnel lens spotlight as claimed in claim 26 , wherein the integrated diffusing glass defines a light mixing system that changes a proportion of scattered light relative to a proportion of optically imaged light as a function of the position of the Fresnel lens spotlight.

28 . The lighting set as claimed in claim 19 , wherein the reflector has a reflector focal point that is remote from the reflector so that the reflector focal point can be superimposed on the virtual focal point in the spot position of the lighting set.

29 . The flashlight as claimed in claim 21 , wherein the ellipsoid reflector has a reflector focal point that is remote from the ellipsoid reflector so that the reflector focal point can be superimposed on the virtual focal point in the spot position of the flashlight.