Abstract: An autofocus apparatus is capable of detecting the position of a sample on a microscope. The sample may consist of a specimen mounted between a microscope slide and coverslip or specimens within a well plate. The device tracks the position of a sample by identifying refractive index boundaries through Fresnel reflections. A change in refractive index can correspond to the top and bottom of a coverslip, the top of a slide, the bottom of a well plate or the bottom of a well within a well plate. Using optical coherence tomography (OCT) these reflections are used to form a depth scan of the sample which gives the positions of these surfaces relative to the objective. The device functions as an autofocus system by compensating for any variation of the position of the sample from the focal plane of the objective.

Abstract: An autofocus apparatus includes a light source; an optical coupler having a first port, second port and a third port; wherein the optic coupler couples to the light source at the first port; an optical collimator for directing a light output from the second port of the optical coupler onto a sample through a Dichroic mirror and a microscope objective, wherein the sample is placed on a substrate supported by an adjustable microscopy stage; a scanning device for focusing the light at a plurality of focal points along an axis; a photodiode detector for converting a reflected light signal into an intensity signal; a memory device for storing a signal template; and a microprocessor for detecting a peak in the intensity signal by cross-correlating the intensity signal with the signal template; wherein the microprocessor generates a command for moving the position of the adjustable microscopy stage along the axis.

Abstract: A variable beam expander, including: a first lens having a first focal length that is adjustable by a control circuit; a second lens having a second focal length that is adjustable by the control circuit; wherein the first lens and the second lens are separated by a fixed distance; and wherein the control circuit is configured to adjust the first and second focal lengths such that the sum of the first and second focal lengths is equal to the fixed distance.

Abstract: An autofocus apparatus includes a light source; an optical coupler having a first port, second port and a third port; wherein the optic coupler couples to the light source at the first port; an optical collimator for directing a light output from the second port of the optical coupler onto a sample through a Dichroic mirror and a microscope objective, wherein the sample is placed on a substrate supported by an adjustable microscopy stage; a scanning device for focusing the light at a plurality of focal points along an axis; a photodiode detector for converting a reflected light signal into an intensity signal; a memory device for storing a signal template; and a microprocessor for detecting a peak in the intensity signal by cross-correlating the intensity signal with the signal template; wherein the microprocessor generates a command for moving the position of the adjustable microscopy stage along the axis.

Abstract: An autofocus apparatus includes, in one embodiment, a light source; a splitter; a fiber optic circulator; an optical collimator; a balance detector; and a microprocessor. The fiber optic circulator couples one of the split light signals at a first port, to the optical collimator at a second port, and to the balance detector at the third port. The optical collimator directs the light beam from the fiber optic circulator onto a sample through a Dichroic mirror and a microscope objective. The balance detector uses another one of the split light signals as an input, and converts a light signal, reflected off of a substrate the sample is placed on, into an analog voltage signal. The microprocessor processes the output of the balance detector and position feedbacks from an adjustable microscopy stage to generate a command for moving the position of the adjustable microscopy stage to achieve a desired focus.

Abstract: A stage comprising a first translation platform having a first axis of motion, and a second translation platform having a second axis of motion, a first linear drive motor for driving the first translation platform in the first axis of motion, and a second linear drive motor for driving the second translation platform in the second axis of motion, wherein each linear drive motor further comprises a coil assembly enclosing a rod stator, and wherein the coil assembly is fixed and the rod stator is movable within the coil assembly.

Abstract: An autofocus apparatus includes, in one embodiment, a light source; a splitter; a fiber optic circulator; an optical collimator; a balance detector; and a microprocessor. The fiber optic circulator couples one of the split light signals at a first port, to the optical collimator at a second port, and to the balance detector at the third port. The optical collimator directs the light beam from the fiber optic circulator onto a sample through a Dichroic mirror and a microscope objective. The balance detector uses another one of the split light signals as an input, and converts a light signal, reflected off of a substrate the sample is placed on, into an analog voltage signal. The microprocessor processes the output of the balance detector and position feedbacks from an adjustable microscopy stage to generate a command for moving the position of the adjustable microscopy stage to achieve a desired focus.

Abstract: A stage comprising a first translation platform having a first axis of motion, and a second translation platform having a second axis of motion, a first linear drive motor for driving the first translation platform in the first axis of motion, and a second linear drive motor for driving the second translation platform in the second axis of motion, wherein each linear drive motor further comprises a coil assembly enclosing a rod stator, and wherein the coil assembly is fixed and the rod stator is movable within the coil assembly.

Abstract: An autofocus apparatus includes, in one embodiment, a light source; a splitter; a fiber optic circulator; an optical collimator; a balance detector; and a microprocessor. The fiber optic circulator couples one of the split light signals at a first port, to the optical collimator at a second port, and to the balance detector at the third port. The optical collimator directs the light beam from the fiber optic circulator onto a sample through a Dichroic mirror and a microscope objective. The balance detector uses another one of the split light signals as an input, and converts a light signal, reflected off of a substrate the sample is placed on, into an analog voltage signal. The microprocessor processes the output of the balance detector and position feedbacks from an adjustable microscopy stage to generate a command for moving the position of the adjustable microscopy stage to achieve a desired focus.

Abstract: The concentration of at least one luminescence-affecting chemical species in at least one location in a sample capable of emitting luminescent radiation can be determined using multiple luminescent emission ratio photometry and multiple luminescent emission ratio imaging. An apparatus and method for conducting multiple luminescent emission ratio photometry and imaging is provided.