| abstract |
A retinal camera 101 is used to examine an eye 10 , the camera including a light source 1 having first and second sources 21, 22 emitting first and second wavelength bands. The first and second light sources are arranged to alternately produce light onto the retina such that the absorptivity of light of the first wavelength band by oxygenated blood is greater than the absorptivity of light of the second wavelength band, and the absorptivity of light of the first wavelength band by the oxygenated blood is less than the absorptivity of light of the second wavelength band. Light is selectively focused from the first and second sources by an optical arrangement 30, 50, 60, 80 and 90 and imaging devices 90, 120, 130 produce respective images of a portion of the retina illuminated with the respective wavelength bands. The images obtained by the imaging device are processed by the imaging device and processor 140 to determine a retinal metabolic image based on haemoglobin oxygenation. In an embodiment of the invention light is scanned across the retina. |