Apparatus and associated methods relate to autonomous devices configured to map surface topologies of airfoils of gas turbine engines. The autonomous device moves across the airfoil while remaining coupled thereto while sensing the surface topology of the airfoil using an optical gel sensor via an array of airfoil contacting members. The optical gel sensor includes an optical gel, having nominally planar opposite surfaces defining a nominal gel thickness extending over an image area. A lighting element illuminates the optical gel from an end of the flexible optical gel. A plurality of airfoil contacting members extend between the flexible optical gel and the airfoil, thereby distorting the flexible optical gel in response to changes in the surface topology of the airfoil. A two-dimensional imager images the flexible optical gel over the image area, thereby creating a two-dimensional image that is indicative of the surface topology.

An apparatus for carrying our spectroscopy configured to obtain a spectrum beam from an interaction between a laser beam and a sample. The apparatus includes an optical system that guides the spectrum beam to a diffraction element of the optical system that is configured to split the spectrum beam into a spectrum of spatially separated wavelength components associated with the sample. A detector with an array of pixels for detecting the spectrum of spatially separated wavelength components on pixels of the array of pixels and a data acquisition device coupled to the detector. The data acquisition device carries out measurements, wherein during each measurement data indicative of the spectrum of spatially separated wavelength components is obtained from the detector, wherein the spectrum of spatially separated wavelength components is detected, and determine an averaged spectrum of the sample based on the data obtained during at least some measurements.

An optical coherence tomography apparatus includes a light source for emitting source light, a splitter for dividing the source light into (1-1)-th light and (1-2)-th light, a reference group for receives the (1-1)-th light and including a mirror reflecting the received (1-1)-th light back to the splitter, a sample group for inspecting a display panel using the (1-2)-th light and then reflecting the (1-2)-th light reflected from the display panel back to the splitter, a detector for converting an interference signal into an electrical signal, and a processing unit for receiving the electrical signal from the detector and generating a tomographic image. The splitter generates the interference signal by combining the (1-1)-th light reflected from the reference group and the (1-2)-th light reflected from the sample group. Speed at which the sample group inspects the display panel is variable.