Abstract:
Improved performance in reflectance photometry is obtained by employing an optical fiber to direct collimated light to a test area and to return both diffuse and specular light from the test area. Specular light is prevented from reaching a light detector by a spatial filter, while diffuse light is collected and measured.
Abstract:
A total transmission spectroscopy system for use in determining the analyte concentration in a fluid sample comprises a sample cell receiving area, a light source, a collimating lens, a first lens, a second lens, and a detector. The sample cell receiving area is adapted to receive a sample to be analyzed. The sample cell receiving area is constructed of a substantially optically clear material. The collimating lens is adapted to receive light from the light source and adapted to illuminate the sample cell receiving area with a substantially collimated beam of light. The first lens is adapted to receive regular and scattered light transmitted through the sample at a first angle of divergence. The first lens receives light having a first angle of acceptance. The first lens outputs light having a second angle of divergence. The second angle of divergence is less than the first angle of divergence. The second lens is adapted to receive light from the first lens and adapted to output a substantially collimated beam of light. The detector is adapted to measure the light output by the second lens.
Abstract:
A glucose monitoring system comprising a readhead positioned a predetermined distance from a sample aperture. The readhead comprises first and second LEDs adapted to emit intersecting paths of light. A beam splitter is positioned at the intersection of the light paths. The beam splitter comprises a band pass filter for controlling the center wavelength of a resulting coaxial emitted light for illuminating a sample on the sample aperture. The readhead further comprises a detector which comprises a detector aperture and a molded lens over the detector aperture. A light-scattering section upstream of the lens comprises a plurality of steps having angles greater than 90 degrees to reduce internal stray light.
Abstract:
The high spatial resolution area array detection readhead and method for using the same involve modifying an existing area array detection readhead to provide improved spatial resolution within the sample detection area. One modification involves reducing the field of view of the area array detection readhead. The reduction in the field of view increases pixel spatial resolution because the same number of pixels in the area array detector cover a smaller area. This reduction can be achieved by changing the magnification of the lens of the area array detection readhead or by moving the sample detection area closer to the area array detection readhead. The next modification involves properly aligning the reduced field of view within the sample detection area to take advantage of the improved pixel resolution. Preferably, by rotating the typical area array detection readhead 90 degrees with respect to the sample detection area, the length of the reduced field of view aligns with the width of the sample detection area. Finally, an optical wedge is positioned between the area array detection readhead and the sample detection area. The optical wedge is designed to shift the reduced field of view a predetermined number, X, of degrees from normal along the length of the sample detection area to cover a first field of the sample detection area. By inverting the optical wedge or introducing another optical wedge, the field of view is shifted -X degrees from normal and fills the remaining field of the sample detection area. As such, the sample detection area is divided into two fields that cover the entire sample detection area. Accordingly, by switching the optical wedge between the two wedge positions, the improved area array detection readhead shifts the reduced field of view + and -X degrees to image the entire sample detection area at the higher spatial resolution.
Abstract:
An optical waveguiding optical format enables consistent optical analysis of small sample volumes. The optical format is comprised of an illumination light guide, a read window upon which a sample is placed, a sample collection needle or capillary, and a detection guide. Light redirecting facets are provided within the format itself such that the format serves as a unitary component for accepting light, directing light through a sample, and emitting light for detection.
Abstract:
Formats for optical analysis of fluid samples are provided with platforms and wells for contacting fluid samples and bringing reagents in contact with fluid samples. Formats may be made in opposing platform-and-well constructions, allowing a platform protruding from one format member to enter a well contained within an opposing format member. A sample fill nose accepts sample fluid from a sample collection opening and transports the sample fluid through the format.
Abstract:
A total transmission spectroscopy system for use in determining the analyte concentration in a fluid sample comprises a sample cell receiving area, a light source, a collimating lens, a first lens, a second lens, and a detector. The sample cell receiving area is adapted to receive a sample to be analyzed. The sample cell receiving area is constructed of a substantially optically clear material. The collimating lens is adapted to receive light from the light source and adapted to illuminate the sample cell receiving area with a substantially collimated beam of light. The first lens is adapted to receive regular and scattered light transmitted through the sample at a first angle of divergence. The first lens receives light having a first angle of acceptance. The first lens outputs light having a second angle of divergence. The second angle of divergence is less than the first angle of divergence. The second lens is adapted to receive light from the first lens and adapted to output a substantially collimated beam of light. The detector is adapted to measure the light output by the second lens.
Abstract:
A method of determining auto-calibrating information of a test sensor includes providing an optical read head that includes a light source, a light guide and a detector. The read head forms an opening that is sized to receive a test sensor. The detector includes a linear-detector array or single detector. A test sensor is provided having apertures formed therein. The test sensor is placed in the opening of the optical read head. Light is transmitted from the light source through the apertures. The light transmitted through the apertures using the detector or detecting the absence of light being transmitted through the test sensor using the detector is detected. The detected light or the absence of detected light information from the detector is used to determine the auto-calibration information of the test sensor.
Abstract:
A total transmission spectroscopy system for use in determining the analyte concentration in a fluid sample comprises a sample cell receiving area, a light source, a collimating lens, a first lens, a second lens, and a detector. The sample cell receiving area is adapted to receive a sample to be analyzed. The sample cell receiving area is constructed of a substantially optically clear material. The collimating lens is adapted to receive light from the light source and adapted to illuminate the sample cell receiving area with a substantially collimated beam of light. The first lens is adapted to receive regular and scattered light transmitted through the sample at a first angle of divergence. The first lens receives light having a first angle of acceptance. The first lens outputs light having a second angle of divergence. The second angle of divergence is less than the first angle of divergence. The second lens is adapted to receive light from the first lens and adapted to output a substantially collimated beam of light. The detector is adapted to measure the light output by the second lens.
Abstract:
A fluid sensor comprises a formed plastic body and a reagent. The body has a top face with an integral first surface. The body also has a bottom face opposed to the first surface and a sidewall that extends from the periphery of the top face. The first surface is adapted to accept a fluid sample. The reagent is disposed on the integral first surface and causes a color change detectable on the bottom face when the reagent reacts with an analyte in the fluid sample.