A device includes: a first portion configured to be grasped by the hand of the user, and a second portion defining a reservoir containing a control material, wherein the control material contains a target analyte in a known or predetermined concentration. A method of verifying the accuracy of an analyte monitoring device includes receiving a fluid sample, identifying the fluid sample as a control solution, and analyzing the fluid sample.

Instruments, systems, and methods for measuring optical density of microbiological samples are provided. In particular, optical density instruments providing improved safety, efficiency, comfort, and convenience are provided. Such optical density instruments include a handheld portion and a base station. The optical density instruments may be used in systems and methods for measuring optical density of biological samples.

A device may determine a calibration value for a spectrometer using light from a first light source; deactivate the first light source after determining the calibration value; perform measurement with regard to a sample based on the calibration value, wherein the measurement of the sample is performed using light from a second light source; determine that the calibration value is to be updated; and update the calibration value using the light from the first light source.

Instruments, systems, and methods for measuring optical density of microbiological samples are provided. In particular, optical density instruments providing improved safety, efficiency, comfort, and convenience are provided. Such optical density instruments include a handheld portion and a base station. The optical density instruments may be used in systems and methods for measuring optical density of biological samples.

A method, computer program product, and apparatus are provided for controlling components of a detection device. The device may detect turbidity of liquid with sensors such as a density sensor and/or nephelometric sensor. A light modulation pattern may reduce or eliminate interference in sensor readings. Readings may be performed during off cycles of an illumination light to reduce interference but to provide improved visibility of a tube. Dark and light sensor readings may be performed with an emitter respectively off or on to account for ambient light in subsequent readings. Readings from the density sensor and/or nephelometric sensor may be used to calculate McFarland values. The device may be zeroed based on an emitter level that results in a sensor reading satisfying a predetermined criterion.

Apparatuses and associated methods of manufacturing are described that provide a tip resistant optical testing instrument configured to rest on a surface. The optical testing instrument includes a shell defining a cavity for receiving a sample tube. The shell includes a bottom shell surface, wherein the bottom shell surface defines at least one support element, wherein the at least one support element is configured to engage the surface to support the optical testing instrument in a testing position, and a translational surface configured to engage the surface to support the optical testing instrument in an angled position. In an instance in which the optical testing instrument tilts from the testing position to the angled position, the translational surface is configured to engage the surface contacting the translational surface to prevent the optical testing instrument from tipping further and allow the optical testing instrument to return to the testing position.

A method is disclosed for maintaining a desired optical output in a solid state illumination device, where the device is configured to accommodate multiple light emitting diodes (LEDs) and to combine light from the LEDs to produce a single optical output. The method includes testing the LEDs before adding them into the device. The testing produces characterizing information that describes how one or more optical properties (e.g., optical power and/or peak wavelength) of the tested LED change with temperature. This characterizing information is stored in a computer-based memory of the device, and the tested LED is added (connected) into the device. Then, during operation, temperature sensors measure a temperature associated with each respective LED in the device, and electrical current to one or more of the LEDs can be adjusted based on the measured temperatures associated with each LED and its stored characterizing information.

A method, computer program product, and apparatus are provided for controlling components of a detection device. The device may detect turbidity of liquid with sensors such as a density sensor and/or nephelometric sensor. A light modulation pattern may reduce or eliminate interference in sensor readings. Readings may be performed during off cycles of an illumination light to reduce interference but to provide improved visibility of a tube. Dark and light sensor readings may be performed with an emitter respectively off or on to account for ambient light in subsequent readings. Readings from the density sensor and/or nephelometric sensor may be used to calculate McFarland values. The device may be zeroed based on an emitter level that results in a sensor reading satisfying a predetermined criterion.

Instruments, systems, and methods for measuring optical density of microbiological samples are provided. In particular, optical density instruments providing improved safety, efficiency, comfort, and convenience are provided. Such optical density instruments include a handheld portion and a base station. The optical density instruments may be used in systems and methods for measuring optical density of biological samples.

A device may determine a calibration value for a spectrometer using light from a first light source; deactivate the first light source after determining the calibration value; perform measurement with regard to a sample based on the calibration value, wherein the measurement of the sample is performed using light from a second light source; determine that the calibration value is to be updated; and update the calibration value using the light from the first light source.