Illuminating an environment

1. A method of emitting light from one or more light emitting elements each controllable to emit respective light, the method comprising:

emitting a first time period of photopic light,

followed by emitting a first time period of scotopic light,

followed by emitting a second time period of photopic light, and

followed by emitting a second time period of scotopic light;

wherein a first transition from the first time period of photopic light to the first time period of scotopic light is different compared to a second transition from the second time period of photopic light to the second time period of scotopic light, and/or wherein a third transition from the first time period of scotopic light to the second time period of photopic light is different compared to a fourth transition from the second time period of scotopic light to the first time period of photopic light or to a third time period of photopic light, and

wherein the photopic light and the scotopic light result in photopic vision and scotopic vision respectively.

2. The method according to claim 1 , wherein the first transition occurs over a first transition time period and the second transition occurs over a second, different transition time period and/or the third transition occurs over a third transition time period and the fourth transition occurs over a fourth, different transition time period.

3. The method according to claim 2 , wherein the second transition time period is greater than the first transition time period and/or the fourth transition time period is greater than the third transition time period.

4. The method according to claim 1 , wherein the first transition comprises light of a first intensity profile and the second transition comprises light of a second, different intensity profile.

5. The method according to claim 1 , wherein the first transition comprises light of a first spectral profile and the second transition comprises light of a second, different spectral profile.

6. The method according to claim 1 comprising:

repeating a light cycle, wherein the repeated light cycle comprises consecutive periods of photopic and scotopic light comprising at least the first and second time periods of photopic light and the first and second time periods of scotopic light.

7. The method according to claim 6 , wherein the second time period of scotopic light is emitted once per light cycle.

8. The method according to claim 6 , wherein the light cycle is emitted over a time period of one day.

9. The method according to claim 1 , wherein the second time period of scotopic light is greater than the first time period of scotopic light and/or the first and second time periods of photopic light.

10. The method according to claim 1 , wherein the time periods are programmable by an end-user.

11. The method according to claim 1 , wherein the photopic light and scotopic light respectively result in human photopic vision and scotopic vision and provide an illuminance above 30 lx and an illumination below a few lux, respectively.

12. The method according to claim 1 , wherein the photopic light and scotopic light respectively result in chicken photopic vision and scotopic vision.

13. The method according to claim 1 , wherein the light emitted from the one or more light emitting devices is optical light.

14. A computer program product comprising code embodied on a non-transitory computer-readable storage medium and configured to cause at least one processor to perform the method of claim 1 by controlling the one or more light emitting elements when the at least one processor executes the code.

15. The method of claim 1 , wherein one of the first transition and the second transition lasts at least six times longer than the other of the first transition and the second transition, and wherein one of the third transition and the fourth transition lasts at least six times longer than the other of the third transition and the fourth transition.

16. A lighting system comprising one or more light emitting elements each controllable to emit respective light and configured to:

emit a first time period of photopic light,

followed by emitting a first time period of scotopic light,

followed by emitting a second time period of photopic light, and followed by emitting a second time period of scotopic light;

wherein a first transition from the first time period of photopic light to the first time period of scotopic light is different compared to a second transition from the second time period of photopic light to the second time period of scotopic light, and/or wherein a third transition from the first time period of scotopic light to the second time period of photopic light is different compared to a fourth transition from the second time period of scotopic light to the first time period of photopic light or a third time period of photopic light; and

wherein the photopic light and the scotopic light result in photopic vision and scotopic vision respectively.

17. The system of claim 16 , wherein one of the first transition and the second transition lasts at least six times longer than the other of the first transition and the second transition, and wherein one of the third transition and the fourth transition lasts at least six times longer than the other of the third transition and the fourth transition.