Abstract:
The present invention relates to an apparatus for use in the determination of a condition or state of an object based on quasi-elastic interaction between the object and light transmitted to the object, the apparatus comprising a beam splitter arrangement for splitting an incoming light beam of wavelength, λ, into a diffracted light beam and an undiffracted light beam, the beam splitter arrangement comprising a first and a second diffractive member, the first diffractive member transforming the light beam emitted by the light source into the diffracted and the undiffracted light beams, the second diffractive member receiving the diffracted light beam and diffracting the received light beam in a direction substantially parallel to the undiffracted light beam from the first diffractive member, wherein the diffracted light beam, after being diffracted by the second diffractive member, and the undiffracted light beam from the first diffractive member are separated by a distance, d, said distance, d, being dependent on wavelength, λ.
Abstract:
A lighting device (7) for illuminating objects, the lighting device comprising: a plurality of light emitting diodes (1) wherein at least one of the plurality of light emitting diodes is adapted to generate light having a spectrum different from a spectrum of light generated by another light emitting diode of said plurality of light emitting diodes; and a chamber (8) comprising a first reflective surface (3a) and an opening (5) for allowing light to exit said chamber, said opening having a periphery, wherein the plurality of light emitting diodes (1) are positioned along the periphery of said opening. The opening (5) has a centre point defined as the centroid of said opening, and that said plurality of light emitting diodes are positioned along a limited portion of the periphery of said opening, wherein an angular distance between any two light emitting diodes of said lighting device relative the centre point of the opening is smaller than 135 degrees and said first reflective surface (3a) is a diffuse reflective surface.
Abstract:
The present invention relates to an apparatus for the determination of a condition or state of an object based on quasi-elastic interaction between the object and light transmitted to the object, the apparatus comprising a diffractive optical element having a diffracting region comprising a first diffracting structure for diffraction and focussing of a first light beam to the object, and a second diffracting structure that is laterally displaced relative to the first diffracting structure for diffraction and focussing of a second light beam to the object. The first and second diffracting structures focus the first and second light beams in the same focussing plane, the focussing plane being substantially perpendicular to propagation directions of the first and second light beams. The diffracting region further comprises a receiving diffracting structure for diffraction of light from the light beams that has interacted with the object. The diffracted light is diffracted in a diffraction angle. The size of the diffraction angle is substantially equal to the angle of incidence of the incoming light beam.