A cell counter comprising: (i) a bright-field light source; (ii) an imaging system (122, 222) configured to image, detect, and count cells; and (iii) a sample mounting system comprising upper and lower sample surfaces configured for direct receipt of a cell suspension for counting, the system comprising: a base having a base top side, a base bottom side, and an objective lens cavity located on the base so as to align with and receive an objective lens of the imaging system (122, 222); a hinge fixed to the base; a movable arm fixed to the hinge, said movable arm having a movable arm top side, a movable arm bottom side, and a bright-field light source cavity located on a portion of the movable arm distal to the hinge and configured to receive the bright-field light source; the lower sample surface mounted to the base top side in a position configured to receive bright-field light from the bright-field light source when the movable arm is in a closed position; and the upper sample surface mounted to the movable arm bottom side of the movable arm in a position configured to receive bright-field light from the bright field light source; wherein a distance between the lower sample surface and the upper sample surface when the movable arm is in the closed position is adjustable to accommodate variable volumes of cell suspension samples deposited between the upper and lower sample surfaces; and wherein the system is re-usable by moving the movable arm to an open position and cleaning the sample surfaces (101, 102). (i) a bright-field light source; (ii) an imaging system (122, 222) configured to image, detect, and count cells; and (iii) a sample mounting system comprising upper and lower sample surfaces configured for direct receipt of a cell suspension for counting, the system comprising: a base having a base top side, a base bottom side, and an objective lens cavity located on the base so as to align with and receive an objective lens of the imaging system (122, 222); a hinge fixed to the base; a movable arm fixed to the hinge, said movable arm having a movable arm top side, a movable arm bottom side, and a bright-field light source cavity located on a portion of the movable arm distal to the hinge and configured to receive the bright-field light source; the lower sample surface mounted to the base top side in a position configured to receive bright-field light from the bright-field light source when the movable arm is in a closed position; and the upper sample surface mounted to the movable arm bottom side of the movable arm in a position configured to receive bright-field light from the bright field light source; wherein a distance between the lower sample surface and the upper sample surface when the movable arm is in the closed position is adjustable to accommodate variable volumes of cell suspension samples deposited between the upper and lower sample surfaces; and wherein the system is re-usable by moving the movable arm to an open position and cleaning the sample surfaces (101, 102). a base having a base top side, a base bottom side, and an objective lens cavity located on the base so as to align with and receive an objective lens of the imaging system (122, 222); a hinge fixed to the base; a movable arm fixed to the hinge, said movable arm having a movable arm top side, a movable arm bottom side, and a bright-field light source cavity located on a portion of the movable arm distal to the hinge and configured to receive the bright-field light source; the lower sample surface mounted to the base top side in a position configured to receive bright-field light from the bright-field light source when the movable arm is in a closed position; and the upper sample surface mounted to the movable arm bottom side of the movable arm in a position configured to receive bright-field light from the bright field light source; wherein a distance between the lower sample surface and the upper sample surface when the movable arm is in the closed position is adjustable to accommodate variable volumes of cell suspension samples deposited between the upper and lower sample surfaces; and wherein the system is re-usable by moving the movable arm to an open position and cleaning the sample surfaces (101, 102).