Optical module and mobile device having same

A mobile device, comprising:

• a housing;
• and
• an optical module in the housing, the optical module comprising:
• a micro spectrometer comprising:
• an optical crystal, the optical crystal being configured to receive detection light and covert the detection light into interference light, the optical crystal being surrounded by a sleeve, the sleeve configured to fix a position of the optical crystal;
• a lens, the lens configured for receiving the interference light and focusing the interference light;
• a photosensitive assembly configured for imaging the interference light into an interference image;
• a controller, the controller electrically connected to the photosensitive assembly, and the controller configured to convert the interference image into light wavelength signals and light intensity signals;
• wherein the optical crystal defines a plurality of slits;
• each of the plurality of slits is configured to make the detection light to interfere and diffract.