Measuring method for wavelength indication errors of ultraviolet and visible spectrophotometer

The invention relates to a measuring method for wavelength indication errors of an ultraviolet and visible spectrophotometer to overcome problems in measurement of any wavelength indication error of the ultraviolet and visible spectrophotometer The method comprises the following steps: calibrating the wavelength of a fiber optic spectrometer and allowing light emitted by the ultraviolet and visible spectrophotometer to converge to light guide inlets of a seven branch-in-one optical fiber via reflection by a reflector lens of a 90-DEG corner lighting device and condensation by a convex lens of the 90-DEG corner lighting device and then to be introduced into the fiber optic spectrometer via the seven branch-in-one optical fiber; and adjusting the location of the 90-DEG corner lighting device in a colorimetric ware groove along a longitudinal direction to allow the spectral energy value of the fiber optic spectrometer to be maximized, fixing a hollow connecting rod into a pressing cap by a tightening a screw, an