Spectrometers can measure light properties up close in controlled environments or from far distances like outer space. An optical spectrometer has three specific functions. The answer is — it depends on what you're measuring. In light measurement, there are generally two situations you should consider: If. The wavelength of a wave describes how far two adjacent peaks are. Long wavelength means the peaks are separated far from each other, and short wavelength means the peaks are closer. The relation between and the frequency of the wave and its wavevector is called the dispersion curve and depends on. Spectrophotometry is a method to measure how much a chemical substance absorbs light by measuring the intensity of light as a beam of light passes through sample solution. By analyzing how much light is absorbed at specific wavelengths, we can learn. Our Resolution Calculator will estimate spectral resolution, bandwidth, and dispersion using the grating equation, but we're commonly asked how slit width, spectrometer imaging performance, and detector pixel size affect this.