A new type of laser scanning confocal microscope (LSCM) holds the promise of diagnosing skin cancer in a single snapshot. Typical LSCMs take 3-D images of thick tissue samples by visualizing thin slices within that tissue one layer at a time. Sometimes scientists supplement these microscopes with spectrographs, which are devices that measure the pattern of wavelengths, or “colors,” in the light reflected off of a piece of tissue. This pattern of wavelengths acts like a fingerprint, which scientists can use to identify a particular substance within the sample. But the range of wavelengths used so far with these devices has been narrow, limiting their uses.