Optical device for facilitating reading

1. An optical device (FILT) comprising:

a control unit (CTRLU) and

a filtering module (LIMOD) adapted for opening and closing a viewing space in a visible light spectrum,

wherein said optical device (FILT) is configured to periodically open and close said viewing space according to successive cycles operated at a frequency Fd, each cycle having a duration T and comprising a viewing space opening period of duration T1 followed or preceded by a viewing space closing period of duration T2,

wherein said frequency Fd is comprised within an interval of values ranging from 60 to 90 Hz and the duration T1 of the viewing space opening periods is comprised within an interval of values ranging from 15 to 35% of the duration T of the cycles;

wherein said cycles reduce mirror images perceived by dyslexic subjects during reading.

2. The optical device (FILT) according to claim 1 , wherein said frequency Fd is comprised within an interval of values ranging from 70 to 85 Hz.

3. The optical device according to claim 1 , wherein the frequency Fd varies over time.

4. The optical device according to claim 3 , wherein the frequency Fd varies by increasing in successive steps up to a maximum value in a first rate, called increasing rate, then varies by decreasing in successive steps to a minimum value in a second rate, called decreasing rate, the increasing and decreasing variations repeating iteratively over time.

5. The optical device according to claim 4 wherein said decreasing rate is equal to said increasing rate.

6. The optical device according to claim 5 , wherein said successive steps are of equal duration.

7. The optical device according to claim 5 , wherein said successive steps vary in duration so that the value of said frequency Fd changes in a triangle, saw, or sinusoidal waveform between said maximum value and said minimum value.

8. The optical device according to claim 1 , wherein the duration T1 of said opening periods of the viewing space varies over time.

9. The optical device (FILT) according to claim 1 , wherein said filtering module (LIMOD) comprises polarizing elements and elements of the liquid crystal type adapted for polarizing the light received, transmitted via said viewing space.

10. The optical device (FILT) according to claim 9 , wherein said polarization of the light received via said viewing space is a vertical polarization.

11. The device according to claim 1 , wherein it is of a type comprised in the list: a pair of eyeglasses, a helmet, a mask, an intermediate screen, a filtering plane configured to be disposed in front or against a rendering screen.

12. The device according to claim 1 , wherein said predetermined frequency is defined by a user of said device.

13. An optical filtering method for facilitating reading of graphic and/or text content on any medium by dyslexic subjects, said method being implemented in an optical device (FILT) comprising a control unit (CTRLU) and a filtering module (LIMOD) adapted for opening and closing a viewing space in a visible light spectrum, said method comprising

periodic openings and closings of a viewing space by successive cycles operated at a predetermined frequency Fd, each cycle having a duration T and comprising a viewing space opening period of duration T1 followed or preceded by a viewing space closing period of duration T2,

wherein said frequency Fd is comprised within an interval of values ranging from 60 to 90 Hz and in that the duration T1 of the viewing space opening periods is comprised within an interval of values ranging from 15 to 35% of the duration T of the cycles;

wherein said cycles reduce mirror images perceived by said dyslexic subjects during reading.

14. The optical filtering method according to claim 13 , according to which said frequency Fd is comprised within an interval of values ranging from 70 to 85 Hz.