Abstract: Apparatus for illuminating the retina of an eye. The apparatus includes an illumination device and a lens system. The illumination device and the lens system combine to provide incident illumination from an apparent point source located within the lens system. The apparatus also includes an illumination transfer device. The illumination transfer device has two foci and the apparent point source of the lens system is provided at a first focus point of the illumination transfer device and an eye is accommodated at a second focus point of the illumination transfer device. The illumination transfer device transfers the incident illumination from the apparent point source into the eye to illuminate the retina.

Abstract: Apparatus for illuminating the retina of an eye. The apparatus includes an illumination device and a lens system. The illumination device and the lens system combine to provide incident illumination from an apparent point source located within the lens system. The apparatus also includes an illumination transfer device. The illumination transfer device has two foci and the apparent point source of the lens system is provided at a first focus point of the illumination transfer device and an eye is accommodated at a second focus point of the illumination transfer device. The illumination transfer device transfers the incident illumination from the apparent point source into the eye to illuminate the retina.

Abstract: Apparatus for illuminating the retina of an eye. The apparatus includes an illumination device and a lens system. The illumination device and the lens system combine to provide incident illumination from an apparent point source located within the lens system. The apparatus also includes an illumination transfer device. The illumination transfer device has two foci and the apparent point source of the lens system is provided at a first focus point of the illumination transfer device and an eye is accommodated at a second focus point of the illumination transfer device. The illumination transfer device transfers the incident illumination from the apparent point source into the eye to illuminate the retina.

Abstract: Apparatus for illuminating the retina of an eye. The apparatus includes an illumination device and a lens system. The illumination device and the lens system combine to provide incident illumination from an apparent point source located within the lens system. The apparatus also includes an illumination transfer device. The illumination transfer device has two foci and the apparent point source of the lens system is provided at a first focus point of the illumination transfer device and an eye is accommodated at a second focus point of the illumination transfer device. The illumination transfer device transfers the incident illumination from the apparent point source into the eye to illuminate the retina.

Abstract: Apparatus for illuminating the retina of an eye. The apparatus comprising an illumination device, a lens system, wherein the illumination device and the lens system combine to provide incident illumination from an apparent point source located within the lens system. The apparatus further comprising an illumination transfer device, wherein the illumination transfer device has two foci and the apparent point source of the lens system is provided at a first focus point of the illumination transfer device and an eye is accommodated at a second focus point of the illumination transfer device, and wherein the illumination transfer device transfers the incident illumination from the apparent point source into the eye to illuminate the retina.

Abstract: An apparatus for determining the wavelength of light emitted by, for example, a laser, includes three photodiodes. One photodiode receives a proportion of the light redirected from the main optical path by a beam splitter. A second photodiode receives a proportion of the light redirected from the main optical path by the beam splitter and passing through a broadband filter. A third photodiode receives light that has been caused to interfere by an interferometric device. The ratio of the light intensities at the first and second photodiodes provide a coarse determination of wavelength, when compared to a lookup table, and the ratio of the light intensities at the first and third photodiodes provide a more exact determination of the wavelength.

Abstract: An apparatus for determining the wavelength of light emitted by, for example, a laser (10), includes three photodiodes (17, 18, 30). One photodiode (17) receives a proportion of the light redirected from the main optical path (16) by a beam splitter (13). A second photodiode (18) receives a proportion of the light redirected from the main optical path (16) by the beam splitter (13) and passing through a broadband filter (21). A third photodiode (30) receives light that has been caused to interfere by an interferometric device (23). The interferometric device (23) is formed of a block having partially reflective surfaces so that part of the light is reflected internally within the block and exits at the same place as it entered so as to interfere with light that was externally reflected by the block at that place.