Optical device and spectral detection apparatus

A spectral detection apparatus, comprising:

• an optical device, comprising an optical waveguide, wherein the optical waveguide comprises:
• a polychromatic light channel configured to transport a polychromatic light beam, and provided with a light incident surface for receiving an incident polychromatic light beam at an input end of the polychromatic light channel;
• a chromatic dispersion device arranged downstream from the polychromatic light channel in an optical path and configured to split the polychromatic light beam from the polychromatic light channel into a plurality of monochromatic light beams;
• and
• a plurality of monochromatic light channels arranged downstream from the chromatic dispersion device in the optical path and configured to respectively conduct the plurality of monochromatic light beams with different colors from the chromatic dispersion device,
• wherein monochromatic light output surfaces are respectively provided at output ends of the plurality of monochromatic light channels and configured to output the monochromatic light beams;
• and
• a measurement device opposite to the optical device,
• wherein the measurement device comprises a microfluidic channel and a plurality of light sensing units;
• the plurality of monochromatic light channels are arranged on one side of the microfluidic channel, the plurality of light sensing units are arranged on the other side of the microfluidic channel opposite to the plurality of monochromatic light channels;
• a light receiving surface of each light sensing unit faces a light output surface of one monochromatic light channel,
• and at least part of the microfluidic channel is arranged between light receiving surfaces of the plurality of light sensing units and light output surfaces of the plurality of monochromatic light channels such that the monochromatic light beams outputted by the monochromatic light channels pass through the microfluidic channel to reach the light sensing units;
• wherein the polychromatic light channel, the chromatic dispersion device, the plurality of monochromatic light channels, the microfluidic channel, and the plurality of light sensing units are arranged on a same substrate, and are arranged in a same layer;
• and
• wherein the optical device further comprises:
• a first cladding layer on a first side surface of the polychromatic light channel;
• and
• a second cladding layer on a second side surface of the polychromatic light channel,
• wherein the second side surface is disposed opposite to the first side surface and closer to the substrate than the first side surface;
• wherein a refractive index of the first cladding layer and a refractive index of the second cladding layer are both less than a refractive index of the polychromatic light channel;
• wherein the first cladding layer further covers the light incident surface of the polychromatic light channel;
• and
• wherein the light incident surface of the polychromatic light channel is substantially perpendicular to the second side surface of the polychromatic light channel;
• wherein a reflective bevel is provided in the first cladding layer, the reflective bevel is located upstream from the light incident surface in the optical path and configured to guide an incident light beam into the light incident surface, and the reflective bevel is located on a side surface of first cladding layer away from the light incident surface of the polychromatic light channel;
• and an included angle is formed between the reflective bevel and the second side surface of the polychromatic light channel, wherein the included angle is an acute angle.