Systems, methods, and apparatuses to image a sample for biological or chemical analysis

A fluidic device holder configured to orient a fluidic device with respect to mutually perpendicular X, Y, and Z-axes, the device holder comprising:

• a support structure configured to receive a fluidic device, the support structure including a base surface that faces in a direction along the Z-axis and is configured to have the fluidic device positioned thereon;
• a plurality of reference surfaces facing in respective directions along an XY-plane;
• an alignment assembly comprising an actuator and a movable locator arm that is operatively coupled to the actuator, the locator arm having an engagement end, the actuator moving the locator arm between retracted and biased positions to move the engagement end away from and toward the reference surfaces, wherein the engagement end presses, in a direction along the XY plane, the fluidic device against the reference surfaces when the locator arm is in the biased position such that the fluidic device is held between the engagement end and the reference surfaces in a fixed position with respect to the support structure, wherein the engagement end rotates within the XY-plane when the locator arm is moved between the retracted and biased positions.