Adjustment of the thickness of a biological fluid being monitored by an optical detection assembly

A system for monitoring a biological fluid, comprising:

• a cassette comprising a body formed of a generally rigid material and defining an observation chamber including a flexible cover;
• and
• an optical detection assembly comprising
• a first fluid-adjustment structure,
• a second fluid-adjustment structure,
• a light source,
• a light detector,
• a controller, and
• a drive mechanism coupled to the controller, wherein
• the observation chamber is positioned between the first and second fluid-adjustment structures,
• the light source is configured to emit light through a thickness of a biological fluid in the observation chamber,
• the light detector is configured to receive at least a portion of the light emitted by the light source after said at least a portion of the light has passed through the biological fluid in the observation chamber, and
• the controller is configured to first actuate the drive mechanism to cause at least a portion of one of the first and second fluid-adjustment structures to move with respect to at least a portion of the other one of the first and second fluid-adjustment structures so as to contact and deform at least a portion of the flexible cover to decrease the thickness of the biological fluid in at least a portion of the observation chamber to zero and to subsequently actuate the drive mechanism to cause said at least a portion of said at least one of the first and second fluid-adjustment structures to move with respect to said at least a portion of the other one of the first and second fluid-adjustment structures so as to increase the thickness of the biological fluid in said at least a portion of the observation chamber from zero to a target thickness.

A system for monitoring a biological fluid, comprising:

• a cuvette comprising a body formed of a generally rigid material and defining an observation chamber including a first open end and a second open end;
• and
• an optical detection assembly comprising
• a first fluid-adjustment structure,
• a second fluid-adjustment structure,
• a light source, and
• a light detector, wherein
• the observation chamber is positioned between the first and second fluid-adjustment structures,
• the light source is configured to emit light through a thickness of a biological fluid in the observation chamber,
• the light detector is configured to receive at least a portion of the light emitted by the light source after said at least a portion of the light has passed through the biological fluid in the observation chamber,
• at least a portion of one of the first fluid-adjustment structure is received by the first open end of the observation chamber, defines a sliding seal with surfaces of the observation chamber, and is configured to move toward and away from the observation chamber so to change the thickness of the biological fluid in at least a portion of the observation chamber, and
• at least a portion of the second fluid-adjustment structure is received by the second open end of the observation chamber, defines a sliding seal with surfaces of the observation chamber, and is configured to move toward and away from the observation chamber so as to change the thickness of the biological fluid in said at least a portion of the observation chamber.