Method for projecting an image

1. A method of projecting an image, the method comprising the steps of,

providing light signal which is configured such that it can be projected onto a display surface to display an image;

oscillating a first reflective surface, on a MEMS micro mirror to scan the light signal over the display surface, using an actuator which is in operable co-operation with the first reflective surface on the MEMS micro mirror, by applying a first actuation signal to the actuator, wherein a rise time or fall time of the first actuation signal in a time-domain representation is inversely proportional to a resonant frequency of oscillation of the first reflective surface.

2. The method according to claim 1 , comprising the step of, oscillating a second reflective surface using a second actuation signal, so that the first and second reflective surfaces oscillate with an amplitudes of oscillation, to scan a light signal over the display surface.

3. The method according to claim 2 , wherein the second reflective surface is oscillated at a frequency which is the resonant frequency of the second reflective surface.

4. The method according to claim 1 , further comprising the step of filtering the first actuation signal.

5. The method according to claim 4 , further comprising the step of compensating for a change in the position of a peak in the first actuation signal, caused by filtering.

6. The method according to claim 2 , wherein, the first and second reflective surfaces are arranged such that they are in optical communication with one another.

7. The method according to claim 2 , wherein, the first reflective surface is oscillated slower than the second reflective surface.

8. The method according to claim 1 , wherein, the first reflective surface is configured to scan light along the horizontal reference.

9. The method according to claim 1 , wherein, the first reflective surface is configured to scan light along the vertical reference.

10. The method according to claim 1 , wherein, the each reflective surface is a mirror.

11. The method according to claim 1 , wherein, the rise time, or fall time, is an integer factor of 1/Fresonant, wherein Fresonant is the resonant frequency of oscillation of the first reflective surface.

12. The method according to claim 1 , wherein, the rise time or fall time is equal to 1/{(Fresonant±f)×N} wherein, Fresonant is the resonant frequency of oscillation of the first reflective surface, N is a chosen constant and f is a variable which compensates for the effects of filtering of the actuation signal and/or compensates for variation in resonant frequency within a batch of first reflective surfaces.

13. The method according to claim 11 , wherein, Fresonant is in the range 1-5000 Hz.

14. The method according to claim 12 , wherein, N is in the range 1-1000.

15. The method according to claim 12 , wherein, f is in the range 0-500 Hz.

16. A method of projecting an image, the method comprising the steps of,

providing light signal which is configured such that it can be projected onto a display surface to display an image;

oscillating a first reflective surface, to scan the light signal over the display surface, using an actuator which is in operable co-operation with the first reflective surface, by applying a first actuation signal to the actuator, wherein a rise time or fall time of the first actuation signal is inversely proportional to a resonant frequency of oscillation of the first reflective surface;

wherein, the rise time or fall time is equal to 1/{(F resonant ±f)×N} wherein, F resonant is the resonant frequency of oscillation of the first reflective surface, N is a chosen constant and f is a variable which compensates for the effects of filtering of the actuation signal and/or compensates for variation in resonant frequency within a batch of first reflective surfaces.