Implementations described herein include a device having a data collection system, an actuation assembly, and a visible target. The data collection system has an illuminator, a detector, and a beam splitter operably coupled to the detector. The actuation assembly is coupled to the illuminator via a holder and has a motor coupled to a linear actuator and a speed governor. The visible target facilitates alignment of the subject's eye with the data collection system. The illuminator illuminates the target tissue with interrogating radiation and the actuation assembly moves the illuminator from a first position to a second position to scan a focal point of the interrogating radiation through a predefined thickness of the target tissue. The detector detects the at least one value of the at least one characteristic of responding radiation received from or reflected from the target tissue and uses such information to determine the onset and duration of a pathological condition.