Device for and method of real-time simulation of atmospheric effects on an image

• US 5,663,832 A
• Filed: 03/03/1995
• Issued: 09/02/1997
• Est. Priority Date: 03/03/1995
• Status: Expired due to Fees

• Current Assignee: The United States of America As Represented By The Secretary of Agriculture
• Original Assignee: The United States of America As Represented By The Secretary of Agriculture
• Inventors: Vorontsov, Mikhail A., Ricklin, Jennifer C., Miller, Walter B.
• Primary Examiner(s): Dzierzynski, Paul M.
• Assistant Examiner(s): CHANG, AUDREY Y
• Application Number:
  US08/401,483
• Time in Patent Office: 914 Days
• Field of Search: 359/558, 359/559, 359/36, 359/316, 359/111, 359/337, 359/338, 359/339, 359/341, 359/346, 348/750, 348/758, 382/210, 382/255, 382/260, 382/264, 356/124.5
• US Class Current: 359/559
• CPC Class Codes: G02B 27/46 Systems using spatial filters

Abstract

The present invention discloses a device for and method of simulating an image in real time under turbulent atmospheric conditions. The present invention is realized by expanding a first laser beam using a microscope-objective and a first lens. The expanded light is then projected onto a first LCLV. Light reflecting from the first LCLV is filtered, focused onto a diaphram, polarized, and directed along a path that is around two meters in length. The light is then split into a first beam and a second beam. The first beam is focused onto an optical fiber bundle which is connected to the first LCLV. One end of the optical fiber bundle is rotated with respect to the other end. The second beam is projected upon a second LCLV. A second laser beam is expanded and projected onto a LCTV. The image is provided to the LCTV. The LCTV image is projected onto, and modulated by the second LCLV. The light reflecting from the second LCLV, which represents a simulation of the image under turbulent atmospheric conditions, is then displayed using a CCD camera.

Claims

1. A device for simulating the effects of turbulent atmospheric conditions on an image, comprising:

a) a first laser;

b) a first microscope-objective disposed in the path of light emanating from said first laser;

c) a first lens disposed in the path of light emanating from said first microscope-objective for expanding the light emanating from said first laser to a width of around twenty millimeters;

d) a first LCLV disposed in the path of expanded light emanating from said first lens, where said first LCLV is tilted so that light reflecting from said first LCLV is separated from the light emanating from said first lens;

e) a prism disposed in the path of the reflected light from said first LCLV;

f) a spatial filter disposed in the path of light emanating from said prism;

g) a second lens disposed in the path of light emanating from said spatial filter, where said second lens has the same focal length as said first lens, where said second lens has a common focal plane with said first lens;

h) a diaphragm disposed in the path of light emanating from said second lens so that an image formed on said first LCLV is formed on the plane of said diaphragm;

i) a first polarizer disposed in the path of light emanating from said diaphragm;

j) a plurality of mirrors disposed in the path of light emanating from said first polarizer, where said plurality of mirrors is arranged so that an optical path of around two meters in length is formed;

k) a beam splitter disposed in the path of light emanating from said plurality of mirrors, for directing light which simulates turbulent atmospheric conditions without disturbing the path of the light;

l) an optical fiber bundle disposed in the path of the undisturbed light emanating from said beam splitter, having a first end of said optical fiber bundle rotated with respect to a second end of said optical fiber bundle, where said second end of said optical fiber bundle is connected to said first LCLV;

m) a third lens disposed in the path of directed light emanating from said beam splitter;

n) an attenuator disposed in the path of light emanating from said third lens;

o) a second LCLV disposed in the path of said attenuator, for projecting light that simulates atmospheric turbulence onto said second LCLV;

p) a second laser;

q) a second microscope-objective disposed in the path of light emanating from said second laser;

r) a fourth lens disposed in the path of light emanating from said second microscope-objective, for expanding the light emanating from said second laser to a width of around twenty millimeters;

s) an LCTV disposed in the path of light emanating from said fourth lens, having an input for accepting the image;

t) a second polarizer disposed in the path of light emanating from said LCTV;

u) a second mirror disposed in the path of light emanating from said second polarizer so that the light emanating from said second polarizer representing the image is passed through said second mirror onto said second LCLV so that light reflecting from said second LCLV represents the image modulated by simulated atmospheric turbulence and so that the light representing the image modulated by simulated atmospheric turbulence is redirected without disturbing the paths of light;

v) a fifth lens disposed in the path of the directed light of said second mirror;

w) a third polarizer disposed in the path of said fifth lens; and

x) an optical display device disposed in the path of said third polarizer for displaying the image as modulated by turbulent atmospheric conditions.

2. The device of claim 1, wherein said first laser is a 100 milliwatt argon laser having a wave length of 514.5 nanometers.

3. The device of claim 1, wherein said first end of said optical fiber bundle is rotated with respect to the second end of said optical fiber bundle by an angle in the range from zero to pi radians.

4. The device of claim 1, wherein said second laser is a He--Ne laser.

5. The device of claim 1, further comprising a computer connected to the input of said LCTV for providing computer generated images to said LCTV.

6. The device of claim 1, wherein said optical display device is a CCD screen.

7. The device of claim 2, wherein said first end of said optical fiber bundle is rotated with respect to the second end of said optical fiber bundle by an angle in the range from zero to pi radians.

8. The device of claim 7, wherein said second laser is a He--Ne laser.

9. The device of claim 8, further comprising a computer connected to the input of said LCTV for providing computer generated images to said LCTV.

10. The device of claim 9, wherein said optical display is a CCD screen.

11. A method of simulating the effects of turbulent atmospheric conditions on an image, comprising the steps of:

a) providing a first laser beam;

b) expanding said first laser beam to a width of around twenty millimeters;

c) focusing the expanded beam of the previous step onto a first LCLV;

d) redirecting the light reflecting from said first LCLV using a prism;

e) filtering the light emanating from said prism;

f) focusing the filtered light of the previous step onto a diaphragm;

g) polarizing the light emanating from said diaphragm;

h) directing the polarized light of the previous step along a path that is around two meters in length;

i) splitting the light emanating from the previous step into a first beam and a second beam;

j) directing the first beam of the previous step onto a first end of an optical fiber bundle;

k) connecting the second end of said optical fiber bundle to said first LCLV;

l) rotating the first end of said optical fiber bundle with respect to the second end of said optical fiber bundle;

m) attenuating the second beam of step (i);

n) focusing the result of the previous step onto a second LCLV;

o) providing a second laser beam;

p) expanding the second laser beam to a width of around twenty millimeters;

q) focusing the expanded light of the previous step onto a LCTV;

r) providing the image to said LCTV;

s) polarizing the light emanating from said LCTV;

t) directing the polarized light of the previous step onto said second LCLV;

u) polarizing the light reflecting from said second LCLV; and

v) displaying the polarized light of the previous step.

12. The method of claim 11, wherein said step of providing a first laser bean is accomplished by providing a first laser beam from a 100 milliwatt argon laser having a wave length of 514.5 nanometers.

13. The method of claim 11, wherein said step of rotating the first end of said optical fiber bundle with respect to the second end of said optical fiber bundle is accomplished by rotating the first end of said optical fiber bundle with respect to the second end of said optical fiber bundle by an angle in the range of from zero to pi radians.

14. The method of claim 11, wherein said step of providing a second laser beam is accomplished by providing a second laser beam from a He--Ne laser.

15. The method of claim 11, wherein said step of providing the image to said LCTV is accomplished by providing a computer image to said LCTV.

16. The method of claim 11, wherein said step of displaying the polarized light is accomplished by displaying the polarized light onto a CCD screen.

17. The method of claim 12, wherein said step of rotating the first end of said optical fiber bundle with respect to the second end of said optical fiber bundle is accomplished by rotating the first end of said optical fiber bundle with respect to the second end of said optical fiber bundle by an angle in the range of from zero to pi radians.

18. The method of claim 17, wherein said step of providing a second laser beam is accomplished by providing a second laser beam from a He--Ne laser.

19. The method of claim 18, wherein said step of providing the image to said LCTV is accomplished by providing a computer image to said LCTV.

20. The method of claim 19, wherein said step of displaying said polarized light reflecting from said second LCLV includes a further step of recording said polarized light reflecting from said second LCLV by displaying said polarized light reflecting from said second LCLV onto a CCD screen.