Selective illumination fundus imaging

1. A non-mydriatic fundus imaging system, comprising:

an illumination unit;

a rolling reset image sensor array, including a plurality of rows of pixels;

a processing unit; and

memory encoding computer executable instructions that, when executed by the processing unit, cause the non-mydriatic fundus imaging system to:

illuminate, with the illumination unit, a first area of a fundus, the first area including one of at least a bottom area of the fundus or at least a top area of the fundus;

while the first area of the fundus is illuminated, expose a first portion of the plurality of rows of pixels;

stop illuminating the first area of the fundus;

illuminate, with the illumination unit, a second area of the fundus, the second area including an other of the bottom area of the fundus or the top area of the fundus, and the bottom area not overlapping the top area; and

while the second area of the fundus is illuminated, expose a second portion of the plurality of rows of pixels.

2. The non-mydriatic fundus imaging system according to claim 1 , wherein the rolling reset image sensor array is a complementary metal oxide semiconductor (CMOS) image sensor array configured for a rolling shutter exposure, with:

the first portion of the plurality of rows of pixels being exposed as the rolling shutter exposure; and

the second portion of the plurality of rows of pixels being exposed as the rolling shutter exposure.

3. The non-mydriatic fundus imaging system according to claim 1 , the illumination unit including a first light source and a second light source.

4. The non-mydriatic fundus imaging system according to claim 3 , the first light source being arranged to at least partially illuminate the first area of the fundus; and

the second light source being arranged to at least partially illuminate the second area of the fundus.

5. The non-mydriatic fundus imaging system according to claim 3 , the first light source being a first light emitting diode array; and

the second light source being a second light emitting diode array.

6. The non-mydriatic fundus imaging system according to claim 5 , a wavelength of the first light emitting diode array being equal to a wavelength of the second light emitting diode array.

7. The non-mydriatic fundus imaging system according to claim 1 , the plurality of rows of pixels having a top portion and a bottom portion; and

the first portion of the plurality of rows of pixels being exposed starting at the top portion of the plurality of rows of pixels.

8. The non-mydriatic fundus imaging system according to claim 7 , the second portion of the plurality of rows of pixels being exposed continuing at a top of the bottom portion of the plurality of rows of pixels.

9. The non-mydriatic fundus imaging system according to claim 1 , the second area overlapping at least a portion of the first area.

10. A method of imaging a fundus under non-mydriatic conditions, the method comprising:

illuminating a first area of the fundus using an illumination unit, the first area including one of at least a bottom area of the fundus or at least a top area of the fundus;

while illuminating the first area of the fundus, exposing a first portion of a plurality of rows of pixels of a global shutter image sensor array;

stopping illuminating the first area of the fundus;

illuminating a second area of the fundus using the illumination unit, the second area including an other of the bottom area of the fundus or the top area of the fundus, and the bottom area not overlapping the top area; and

while illuminating the second area of the fundus, exposing a second portion of the plurality of rows of pixels of the global shutter image sensor array.

11. The method according to claim 10 , wherein exposing the first portion of the plurality of rows of pixels includes exposing the plurality of rows of pixels as a global shutter exposure; and

wherein exposing the second portion of the plurality of rows of pixels includes exposing the plurality of rows of pixels as the global shutter exposure.

12. The method according to claim 11 , wherein illuminating the first area of the fundus includes illuminating a first light source of the illumination unit; and

wherein illuminating the second area of the fundus includes illuminating a second light source of the illumination unit.

13. The method according to claim 11 , further comprising reading out the first portion of the plurality of rows of pixels as global shutter readout, wherein reading out the first portion of the plurality of rows of pixels occurs in parallel with stopping illuminating the first area of the fundus.

14. The method according to claim 13 , further comprising:

reading out the second portion of the plurality of rows of pixels as global shutter readout; and

stopping illuminating the second area of the fundus, wherein reading out the second portion of the plurality of rows of pixels occurs in parallel with stopping illuminating the second area of the fundus.

15. A non-mydriatic fundus imaging apparatus, comprising:

a first light-emitting diode (LED) array;

a second LED array;

an image sensor array including a plurality of rows of pixels, the image sensor array configured for global shutter operation;

a processing unit; and

memory storing instructions that, when executed by the processing unit, cause the non-mydriatic fundus imaging apparatus to:

during a first time period, illuminate the first LED array, the first LED array being configured to illuminate a first area of an eye fundus, the first area including one of at least a bottom area of the fundus or at least a top area of the fundus;

capture a first image by exposing, during the first time period, the plurality of rows of pixels as global shutter operation;

during a second time period, illuminate the second LED array, second LED array being configured to illuminate a second area of the eye fundus, the second area including an other of the bottom area of the fundus or the top area of the fundus, and the bottom area not overlapping the top area; and

capture a second image by exposing, during the second time period, the plurality of rows of pixels as global shutter operation.

16. The non-mydriatic fundus imaging apparatus according to claim 15 , the memory further storing instructions that, when executed by the processing unit, cause the non-mydriatic fundus imaging apparatus to generate a composite image by processing the first image and the second image.

17. The non-mydriatic fundus imaging apparatus according to claim 15 , with the first area further including a left side portion of the eye fundus and the second area further including a right side portion of the eye fundus.