Spectrometer

A spectrometer comprising:

• a base;
• a light input disposed on the base for receiving an optical signal;
• a reflector disposed on the base for incidence of the optical signal received by the light input and reflecting the incident optical signal;
• a planar optical grating disposed on the base for incidence of the optical signal reflected by the reflector, and configured to split the optical signal into a plurality of spectral components;
• a focusing mirror disposed on the base for focusing the plurality of spectral components split by the planar optical grating;
• an image sensor disposed on the base, and comprising a sensing surface for receiving the plurality of spectral components focused by the focusing mirror, wherein the sensing surface extends along the base, wherein a virtual central line is defined on the sensing surface and is defined as a virtual line connected by centers of all wavelengths of the plurality of spectral components, a virtual vertical line is defined on the sensing surface to be perpendicular to the virtual central line, and a virtual plane is defined along the virtual vertical line to be perpendicular to the sensing surface, the plurality of spectral components are divided on the sensing surface into a first part of the plurality of spectral components within a first wavelength interval having excessively high light intensity and a second part of the plurality of spectral components within a second wavelength interval having non-excessively-high light intensity according to a preliminary frequency spectrum of the optical signal, the first and second parts of the plurality of spectral components are both signally receivable on the sensing surface;
• a shader having a non-ring shape, and disposed between the focusing mirror and the image sensor, wherein the shader is located on a projection path of the first part of the plurality of spectral components rather than being located on a projection path of the second part of the plurality of spectral components, a shadow generated by the shader falls on an area of the sensing surface corresponding to the first part of the plurality of spectral components for suppressing the first part of the plurality of spectral components rather than falling on another area of the sensing surface corresponding to the second part of the plurality of spectral components, a divergence angle of a light path of each spectral component out of the second part of the plurality of spectral components along the virtual plane is unchanged after the shader is disposed in the spectrometer while a divergence angle of a light path of each spectral component out of the first part of the plurality of spectral components along the virtual plane is reduced after the shader is disposed in the spectrometer;
• and
• a mounting part disposed on the base, and the shader being disposed on the mounting part so that the shader is disposed on the base via the mounting part, wherein the mounting part comprises an adjusting structure configured to adjust a setting angle or a setting position of the shader relative to the base.