摘要:
A transmitted light refractometer comprises an optical system having a movable mirror for redirecting light transmitted through a light-refracting sample to a beam splitter for dividing the light between first and second detection paths. The first detection path leads to an eyepiece whereby an operator may view an illumination boundary shadowline brought into the field of view of the eyepiece by adjusting the position of the movable mirror. The second detection path leads to a light-sensitive detector, preferably a linear scanned array, for generating signal information indicative of the location of the shadowline on the detector. An optical position sensor associated with the movable mirror includes a position detector providing signal information indicative of the position of the movable mirror. During a reading, the shadowline is brought into the field of view of the eyepiece, and the shadowline signal information and the mirror position signal information are processed to calculate index of refraction of the sample.
摘要:
An optical configuration for measuring a difference in refractive index between a first sample and a second sample comprises partitioned first and second optical interfaces symmetrically illuminated by an illumination beam to provide first and second partial beams defined by the refractive index of the first and second samples, respectively. A linear scanned array is aligned in a meridional plane of the optical configuration for detection purposes, and an optical multiplexor is provided upstream of the linear scanned array for receiving the first and second partial beams and defining first and second optical channels carrying optical signal information corresponding to the first and second partial beams. The optical multiplexor switches between optical channels, such that the linear scanned array detects either the first or second optical channel at a given time. Thus, differential measurements are possible using a single linear array. Embodiments for critical angle and surface plasmon resonance refractive index measurements are disclosed. The disclosure also relates to methods for measuring a difference in refractive index between a first sample and a second sample in accordance with the described optical configuration embodiments.
摘要:
An optical configuration for differential refractive index measurements of a test sample relative to a reference sample comprises an optical path along which an illumination beam travels to simultaneously illuminate a pair of optical interfaces on opposite sides of a meridional plane corresponding to the test sample and reference sample, respectively. Partial beams leaving the optical interfaces are optically diverged to illuminate different segments of a linear scanned array aligned in the meridional plane. The difference in location of a pair of shadowlines or a pair of resonance minimums formed by the partial beams on the array provides an indication of the refractive index difference.