1. A method of identifying a potential security threat in a space, the method comprising: (a) collecting a first scan of the space during a first time interval, comprising (i) illuminating at least a portion of the space with energy from an energy source at an illumination angle, such that the energy is reflected from a surface in the space; (ii) detecting an incident angle of the reflected energy with a detector disposed at a known distance from the energy source; (iii) calculating a distance from the surface to the energy source based on the incident angle; (iv) repeating steps (i)-(iii) for a plurality of different locations in the space; (v) generating a first map of the space for the first time interval; (b) collecting a second scan of the space at a second time interval, comprising repeating steps (a)(i)-(a)(v) above during the second time interval to generate a second map of the space; (c) comparing the first map to the second map to determine a change in the space; and (d) determining if a potential security threat is present based on the change in the space.