Optical imaging or spectroscopy systems and methods

An imaging device, comprising:

• an objective;
• a light source;
• a scanning/de-scanning optical assembly having a first moving light-redirecting element that routes illumination light from the light source, through the objective in a proximal-to-distal direction, and scans a resulting beam across a target region;
• a light detector with a one or two dimensional array of detector elements, each providing a respective luminance signal;
• the scanning/de-scanning optical assembly being arranged with respect to the objective, the light source, and the light detector such that after light received from the target region passes through the objective in a distal-to-proximal direction, the first moving light-redirecting element routes the received light to the light detector such that optical responses arising at multiple depths in the target region are concurrently imaged onto respective different detector elements within the light detector, such that a resulting image resolves depth information about the optical responses at the multiple depths, with optical responses obtained at distances that are farther from the incident light beam location corresponding to light that has penetrated more deeply into the target region.