Systems and methods for illumination and imaging of a target

1 . An imaging device for imaging target tissue of a subject comprising:

at least one imaging sensor; and

a wavelength-dependent aperture upstream of the at least one imaging sensor, the wavelength-dependent aperture comprising:

a first aperture portion configured to permit transmission of visible light and fluorescence light, and

a second aperture portion surrounding the first aperture portion and configured to permit transmission of the fluorescence light and block transmission of the visible light, wherein the second aperture portion is configured to block transmission of the visible light through absorption,

wherein the first and second aperture portions are sized such that a depth of field for visible light at the at least one imaging sensor is substantially similar to a depth of field for fluorescence light at the at least one imaging sensor.

2 . The imaging device of claim 1 , wherein the fluorescence light is near infrared (NIR) light.

3 . The imaging device of claim 1 , further comprising a third aperture portion surrounding the first and second aperture portions, wherein the third aperture portion blocks transmission of both the visible and fluorescence light.

4 . The imaging device of claim 1 , wherein the second aperture portion comprises a film and the first aperture portion comprises an opening in the film.

5 . The imaging device of claim 1 , wherein the first aperture portion comprises a first film and the second aperture portion comprises a second film.

6 . The imaging device of claim 5 , wherein the first and second films are disposed on a single substrate.

7 . The imaging device of claim 1 , further comprising at least one lens located downstream of the wavelength dependent aperture.

8 . The imaging device of claim 7 , wherein the wavelength-dependent aperture is located in at least one pupil plane of the at least one lens.

9 . The imaging device of claim 1 , wherein the imaging device comprises a plurality of wavelength-dependent apertures.

10 . The imaging device of claim 1 , wherein the imaging device is an open-field imaging device configured for imaging the target tissue of the subject from outside of the subject.

11 . The imaging device of claim 1 , wherein the visible light comprises ambient light.

12 . A method for imaging target tissue of a subject comprising:

receiving visible light and fluorescence light at a wavelength dependent aperture of an imaging device, at least a portion of the visible and fluorescence light being received from the target tissue of the subject;

transmitting the visible and fluorescence light through a first aperture portion of the wavelength dependent aperture;

transmitting the fluorescence light through a second aperture portion of the wavelength dependent aperture while blocking transmission of the visible light through the second aperture portion of the wavelength dependent aperture through absorption; and

sensing by at least one image sensor the visible and fluorescence light transmitted through the wavelength dependent aperture, wherein the first and second aperture portions are sized such that a depth of field for visible light at the at least one imaging sensor is substantially similar to a depth of field for fluorescence light at the at least one imaging sensor.

13 . The method of claim 12 , wherein the fluorescence light is near infrared (NIR) light.

14 . The method of claim 12 , further comprising blocking transmission of both visible and fluorescence light through a third aperture portion of the wavelength dependent aperture.

15 . The method of claim 12 , wherein the second aperture portion comprises a film and the first aperture portion comprises an opening in the film.

16 . The method of claim 12 , wherein the first aperture portion comprises a first film and the second aperture portion comprises a second film.

17 . The method of claim 16 , wherein the first and second films are disposed on a single substrate.

18 . The method of claim 12 , wherein the imaging device comprises at least one lens located downstream of the wavelength dependent aperture.

19 . The method of claim 18 , wherein the wavelength-dependent aperture is located in at least one pupil plane of the at least one lens.

20 . The method of claim 12 , wherein the imaging device comprises a plurality of wavelength-dependent apertures.

21 . The method of claim 12 , wherein the visible light and fluorescence light are received by the imaging device outside of the subject.

22 . The method of claim 12 , wherein the visible light comprises ambient light.