An optical transceiver comprising: a coupling assembly; and a condensing assembly, wherein the coupling assembly comprises a first surface and a second surface that are oppositely disposed and wherein multiple first lenses are disposed on the first surface; the condensing assembly comprises a fastener, multiple filters, a reflector, and a light passing region; the fastener comprises a third surface and a fourth surface that are oppositely disposed; the multiple filters and the light passing region are disposed on the third surface; the light passing region is located on a side of the multiple filters; the reflector is disposed on the fourth surface; the condensing assembly is fastened to the second surface; the multiple filters are optically aligned with the multiple first lenses separately; each of the multiple filters comprises a pair of light outgoing/incoming surfaces and a pair of side surfaces; the pair of side surfaces are connected between the pair of light outgoing/incoming surfaces; the pair of light outgoing/incoming surfaces are separately attached to the second surface and the third surface 211); the side surfaces of each of the multiple filters are perpendicular to the first surface; the coupling assembly is configured to receive light of different wavelengths; and the light of different wavelengths enters the fastener through the multiple filters and is multiplexed or demultiplexed by the reflector and the multiple filters, and multiplexed or demultiplexed light enters the coupling assembly through the light passing region; characterised in that an angle is formed between the second surface and the first surface, wherein a range of the angle between the first surface and the second surface is from 6° to 13°; and in that the major axis of each of the multiple first lenses is perpendicular to the first surface. a coupling assembly; and a condensing assembly, wherein the coupling assembly comprises a first surface and a second surface that are oppositely disposed and wherein multiple first lenses are disposed on the first surface; the condensing assembly comprises a fastener, multiple filters, a reflector, and a light passing region; the fastener comprises a third surface and a fourth surface that are oppositely disposed; the multiple filters and the light passing region are disposed on the third surface; the light passing region is located on a side of the multiple filters; the reflector is disposed on the fourth surface; the condensing assembly is fastened to the second surface; the multiple filters are optically aligned with the multiple first lenses separately; each of the multiple filters comprises a pair of light outgoing/incoming surfaces and a pair of side surfaces; the pair of side surfaces are connected between the pair of light outgoing/incoming surfaces; the pair of light outgoing/incoming surfaces are separately attached to the second surface and the third surface 211); the side surfaces of each of the multiple filters are perpendicular to the first surface; the coupling assembly is configured to receive light of different wavelengths; and the light of different wavelengths enters the fastener through the multiple filters and is multiplexed or demultiplexed by the reflector and the multiple filters, and multiplexed or demultiplexed light enters the coupling assembly through the light passing region; characterised in that an angle is formed between the second surface and the first surface, wherein a range of the angle between the first surface and the second surface is from 6° to 13°; and in that the major axis of each of the multiple first lenses is perpendicular to the first surface.