Abstract: A broadband radio frequency signal optical fiber phase-stable transmission system includes a local end and a remote end connected by a dispersion compensation module and an optical fiber. The local end modulates a first auxiliary signal whose frequency is half of the frequency of the to-be-transmitted signal and a second auxiliary signal whose frequency is 1.5 times the frequency of the to-be-transmitted signal through the optical carrier and filters out a lower sideband to obtain an optical signal containing only the optical carrier, a first signal, and a second signal corresponds to the optical signal of the first-order upper sideband. The optical signal is transmitted to the remote end through the dispersion compensation module and the optical fiber.

Abstract: The present disclosure provides a TO-CAN cap. The TO-CAN cap includes a casing, the casing has a hollow cylindrical structure, and an inner wall of the casing has a protrusion portion at a first end portion in an axial direction of the casing; and an optical lens, the optical lens has an optical portion for refracting light and a rib portion at a periphery of the optical portion, a side surface of the rib portion having a concave portion complementary to the protrusion portion, where the casing and the optical lens are connected to each other through the protrusion portion and the concave portion.

Abstract: The present disclosure provides an ocular assembly. The ocular assembly including sequentially along an optical axis from an object side to an image side: a first lens with a positive refractive power has a convex object-side surface, and a second lens has a concave image-side surface, wherein at least one of the object-side surface of the first lens, an image-side surface of the first lens, an object-side surface of the second lens, and an image-side surface of the second lens is a Fresnel structure surface, wherein half of a maximal field-of-view HFOV of the ocular assembly satisfies: HFOV>40°, an axial distance TTL of the object-side surface of the first lens to the image plane and a total effective focal length f of the ocular assembly satisfy 1<TTL/f<1.5.

Abstract: The present disclosure provides a TO-CAN cap. The TO-CAN cap includes a casing, the casing has a hollow cylindrical structure, and an inner wall of the casing has a protrusion portion at a first end portion in an axial direction of the casing; and an optical lens, the optical lens has an optical portion for refracting light and a rib portion at a periphery of the optical portion, a side surface of the rib portion having a concave portion complementary to the protrusion portion, where the casing and the optical lens are connected to each other through the protrusion portion and the concave portion.

Abstract: The present invention provides an eyepiece. The eyepiece is composed of one lens, which comprises a first surface and a second surface that are opposite, wherein, the first surface is a curved surface, and the second surface is a Fresnel structure surface; the Fresnel structure surface is formed by a plurality of annular zones that are sequentially arranged, to form a sawtooth surface, and each of the annular zones is formed by a working surface and a non-working surface, the working surface is an aspheric surface, and the non-working surface is a straight bevel; and the eyepiece satisfies the following conditional expression: 85°<FOV<130°, and 0°??i?5°; wherein, FOV is a maximum angle of view of the eyepiece, and ?i is the angle between the non-working surface of the ith annular zone and the optical axis.

Abstract: The present invention provides an eyepiece. The eyepiece is composed of one lens, which comprises a first surface and a second surface that are opposite, wherein, the first surface is a curved surface, and the second surface is a Fresnel structure surface; the Fresnel structure surface is formed by a plurality of annular zones that are sequentially arranged, to form a sawtooth surface, and each of the annular zones is formed by a working surface and a non-working surface, the working surface is an aspheric surface, and the non-working surface is a straight bevel; and the eyepiece satisfies the following conditional expression: 85°<FOV<130°, and 0°??i?5°; wherein, FOV is a maximum angle of view of the eyepiece, and ?i is the angle between the non-working surface of the ith annular zone and the optical axis.

Abstract: The present disclosure provides an ocular assembly. The ocular assembly including sequentially along an optical axis from an object side to an image side: a first lens with a positive refractive power has a convex object-side surface, and a second lens has a concave image-side surface, wherein at least one of the object-side surface of the first lens, an image-side surface of the first lens, an object-side surface of the second lens, and an image-side surface of the second lens is a Fresnel structure surface, wherein half of a maximal field-of-view HFOV of the ocular assembly satisfies: HFOV>40°, an axial distance TTL of the object-side surface of the first lens to the image plane and a total effective focal length f of the ocular assembly satisfy 1<TTL/f<1.5.