System including auto-alignment

A method of controlling a system comprising:

• an input optical path configured to input an excitation light to a target to generate an emission light containing information related to components contained in the target using a nonlinear optical method, and
• a signal obtaining module for obtaining signals containing the information related to the components contained in a target from the emission light propagated forward through the target,
• wherein the signal obtaining module includes:
• a detector to which the emission light is input for generating the signals from the emission light;
• a receiving optical path that guides the emission light and a residual light, which is at least a part of the excitation light propagated forward through the target with the emission light, coaxially between the target and the detector;
• a separator that separates the residual light from the receiving optical path and directs the residual light to an image sensor;
• an optical path that guides the separated residual light to the image sensor;
• and
• an actuator for controlling an optical relative position between the target and the detector, and
• the method includes controlling the actuator to maintain an optical alignment between the target and the detector that detects the emission light filtered by the separator according to a detection result of the separated residual light on the image sensor.

A program product for controlling a system comprising:

• an input optical path configured to input an excitation light to a target to generate an emission light containing information related to components contained in the target using a nonlinear optical method, and
• a signal obtaining module for obtaining signals containing the information related to the components contained in a target from the emission light propagated forward through the target,
• wherein the signal obtaining module includes:
• a detector to which the emission light is input for generating the signals from the emission light;
• a receiving optical path that guides the emission light and a residual light, which is at least a part of the excitation light propagated forward through the target with the emission light, coaxially between the target and the detector;
• a separator that separates the residual light from the receiving optical path and directs the residual light to an image sensor;
• an optical path that guides the separated residual light to the image sensor;
• and
• an actuator for controlling an optical relative position between the target and the detector, and
• the program includes instructions of a controller for controlling the actuator to maintain an optical alignment between the target and the detector that detects the emission light filtered by the separator according to a detection result of the separated residual light on the image sensor.