Optical communication terminal

Abstract

An optical communication terminal, OCT, for optical communication using a laser beam to transmit optical communication signals, the optical communication terminal OCT, comprising: an optical transceiver having an optical transmitter unit adapted to transmit optical communication signals in at least one predefined communication frequency range, and an optical receiver unit adapted to receive optical communication signals in the predefined communication frequency range; and an optical head unit having a telescope provided for collecting optical power and adapting the laser beam diameter, wherein the telescope comprises a monolithic optical telescope lens made of a uniform material being transparent in the communication frequency range and having a high refractive index n.

Description

Technical Field

[0001] This invention relates to the use of laser beams in optical communication terminals to transmit optical communication signals or to realize laser communication using quantum key distribution. Background Technology

[0002] A communication system comprises two or more optical communication terminals for communication with each other. These optical communication terminals are assembled on a fixed platform, such as a mobile phone platform, a manned or unmanned flight platform. The communication link between optical communication terminals can be an end-to-end connection or a network of optical communication terminals, some of which can act as relay stations. Laser communication does indeed complement and / or replace radio frequency (RF) based communication. Compared to traditional RF, laser communication offers higher data transmission rates. Essentially, optical communication terminals (OCTs) support low size, low weight, and low power consumption (SWaP) compared to traditional RF terminals. Therefore, large amounts of data can be efficiently transmitted through the broadband channels of optical communication terminals.

[0003] Figure 1 The communication system (SYS) is clearly demonstrated, including different types of ground-based terminals and adaptable to communication with non-ground communication terminals integrated into different types of manned or unmanned flight platforms. The telecommunications system may also include inter-platform links. High Altitude Platform Systems (HAPS) can communicate with each other through related communication terminals. Aircraft can communicate directly with ground terminals or indirectly through relay communication terminals, such as... Figure 1 As shown. Ground terminals can be located in fixed positions or integrated into movable objects or vehicles, such as trains or ordinary cars. Figure 1 As shown. Handheld mobile user equipment (UE) and ground terminals can also communicate via near-ground flight communication terminals, such as... Figure 1 As shown. The flight platform in the communication system SYS can also provide a communication access point to any location on Earth, even if there is no terrestrial telecommunications network at that location.

[0004] Optical communication terminals are highly sensitive to hardware vibrations and mechanical forces generated on the flight platform. Furthermore, the transport space for optical communication terminals is extremely limited. Summary of the Invention

[0005] Therefore, the purpose of this invention is to provide an optical communication terminal that is adaptable to mechanical forces during transportation and does not occupy much transportation space.

[0006] According to a first aspect, the present invention provides an optical communication terminal for transmitting optical communication signals using a laser beam, the optical communication terminal comprising: An optical transceiver, wherein its optical transmitting unit is adapted to transmit optical communication signals within at least one predefined communication frequency range, its optical receiving unit is adapted to receive optical communication signals within a predefined communication frequency range, and its optical head unit comprises a telescope for collecting optical power and adapted to the diameter of a laser beam, wherein the telescope is a monolithic optical telescope made of a homogeneous material that is transparent and has a high refractive index within the communication frequency range.

[0007] According to a first aspect of the invention, in a possible embodiment of an optical communication terminal, the optical telescope lens of the telescope includes a front surface and a rear surface.

[0008] In a preferred embodiment, the optical telescope lens includes an aspherical convex front surface. In one possible embodiment, the optical communication terminal also includes a spherical or aspherical concave back surface.

[0009] According to a first aspect of the invention, in a possible embodiment of an optical communication terminal, an optical telescope lens is designed to amplify the laser beam transmitted by the optical transmitter unit into the rear surface of the optical telescope lens, and is further designed to reduce the laser beam received through the front surface of the optical telescope lens, wherein the reduced laser beam is output to the optical receiver unit through the rear surface of the optical telescope lens.

[0010] According to a first aspect of the invention, in a further embodiment of the optical communication terminal, the homogeneous material of the optical telescope lens can contain high thermal conductivity. High thermal conductivity can be achieved, particularly when silicon is used as the homogeneous material.

[0011] According to a first aspect of the invention, in a further possible embodiment of the optical communication terminal, the uniform material of the optical telescope lens may include absorption characteristics to reject optical signals with frequencies outside a predefined communication frequency range, thereby minimizing optical noise in the optical receiver unit.

[0012] According to a first aspect of the invention, in a further possible embodiment of the optical communication terminal, the optical telescope lens may include at least one rotationally symmetric section having a side surface surrounding it.

[0013] According to a first aspect of the invention, in a further possible embodiment of the optical communication terminal, the optical telescope lens may include a tapered cross section and / or a cylindrical cross section.

[0014] According to a first aspect of the invention, in a further possible embodiment of the optical communication terminal, the side surface of the conical cross-section of the optical telescope lens may include some suppression elements to suppress backscattered or reflected optical signals.

[0015] According to a first aspect of the invention, in a further possible embodiment of the optical communication terminal, the uniform material of the optical telescope lens comprises silicon.

[0016] In another possible alternative embodiment, the uniform material of the optical telescope lens may include germanium.

[0017] In a further possible alternative embodiment, the uniform material of the optical telescope lens may also include glass.

[0018] According to a first aspect of the invention, in a further possible embodiment of the optical communication terminal, the optical telescope lens is manufactured in a turning manufacturing process.

[0019] According to a first aspect of the invention, in a further possible embodiment of the optical communication terminal, the optical telescope lens may also be manufactured in a grinding process.

[0020] According to a first aspect of the invention, in a further possible embodiment of the optical communication terminal, the optical telescope lens is manufactured in an additive manufacturing process.

[0021] According to a first aspect of the invention, in a further possible embodiment of the optical communication terminal, the optical receiver unit may include a single or composite optical filter and a beam-splitting lens to provide the received optical signal to the tracking sensor of the optical transceiver.

[0022] According to a first aspect of the invention, in a further possible embodiment of the optical communication terminal, the aspherical convex front surface of the optical telescope lens is adapted to receive a laser beam from the coarse pointing component CPA of the optical communication terminal.

[0023] According to a first aspect of the invention, in a further possible embodiment of the optical communication terminal, the frame structure for mounting the optical transceiver and / or the optical communication terminal's optical head unit is manufactured in an additive manufacturing process.

[0024] According to a first aspect of the invention, in a further possible embodiment of the optical communication terminal, the optical head unit may include a dot-front assembly (PAA), a fine pointing assembly (FPA), and / or a dichroic mirror (CBS).

[0025] In one possible embodiment of an optical communication terminal, a dichroic mirror is designed to separate the received light beam from the transmitting unit based on their respective wavelength properties.

[0026] According to a first aspect of the invention, in a further possible embodiment of the optical communication terminal, the optical communication terminal is integrated into a high-altitude platform, an aircraft or drone or other mobile flight station, or may be integrated into a ground station to provide tower-tower communication. Attached Figure Description

[0027] In the following description, possible embodiments of the optical communication terminal according to the present invention are illustrated with reference to the accompanying drawings.

[0028] Figure 1 This describes a communication system that uses a communication terminal to transmit communication signals; Figure 2 A block diagram showing a possible example embodiment of an optical communication terminal according to a first aspect of the present invention is shown; Figure 3 Another example embodiment of an optical communication terminal according to the first aspect of the present invention is shown; Figure 4 A block diagram showing a possible example embodiment of an optical communication terminal according to a first aspect of the present invention is shown; Figure 5 A schematic diagram showing a possible embodiment of an optical system within an optical communication terminal according to a first aspect of the present invention is shown; Figure 6A , 6B An example embodiment of an optical telescope lens for an optical communication terminal according to the first aspect of the present invention is described; Figure 7 This describes possible example embodiments of an optical system having a coarse pointing component (CPA) within an optical communication terminal according to the first aspect of the present invention; Figure 8 A top view of an optical system for an optical communication terminal according to a first aspect of the present invention is shown; Figure 9 An example embodiment of an optical filter and beam splitter lens used in an optical communication terminal according to the present invention is shown; Figure 10 An example embodiment of the optical communication terminal frame structure according to the present invention is shown; Figure 11A , 11B Figures 11C and 11C show cross-sections of different example embodiments of an optical telescope lens used in an optical communication terminal optical system according to the present invention. Detailed Implementation

[0029] like Figure 1 As shown, the optical communication terminal (OCT) 1 can be used in the communication system SYS. For example... Figure 1 As shown, the optical communication terminal 1 can be integrated into high-altitude platforms, aircraft, drones, or other mobile flight stations. The optical communication terminal (OCT) 1 can also be integrated into a ground station to provide tower-tower communication. The optical communication terminal 1 can be used to supplement or replace the radio frequency communication link between a base station and a mobile flight platform. The optical communication terminal 1 provides one or more broadband optical communication channels by transmitting or carrying modulated optical communication signals using a laser beam.

[0030] Figure 2A block diagram of an optical communication terminal 1 according to the present invention is shown. The optical communication terminal 1 includes an optical transceiver 2 and an optical head unit 3. The optical transceiver 2 has an optical transmitting unit 2A, adapted to transmit optical communication signals within at least one predefined communication frequency range. The optical transceiver 2 also includes an optical receiving unit 2B, adapted to receive optical communication signals within the predefined communication frequency range.

[0031] like Figure 2 As shown, the optical communication terminal 1 also includes an optical head unit 3. The optical head unit 3 includes a telescope for collecting optical power and adapting to the laser beam diameter. The telescope of the optical head unit 3 includes a monolithic optical telescope lens made of a homogeneous material, transparent within the communication frequency range, and having a high refractive index n. The optical telescope lens within the optical head unit 3 may include a convex front surface FSUR and a concave back surface RSUR. In a preferred embodiment, the convex front surface of the optical telescope lens within the optical head unit 3 is formed aspherical. The concave back surface of the optical telescope lens may include a spherical or aspherical concave back surface. The optical head unit 3, with its optical telescope TLA, is adapted to receive incoming communication signals carried by the laser beam and can reduce the size of the laser beam diameter to match the size of the optical elements of the optical communication terminal 1. The optical telescope of the optical head unit 3 is also adapted to operate as a beam expander for the transmitted laser beam. In this way, the aperture and secondary collimating lens can be combined into a single component, reducing assembly and integration effort by minimizing the number of components required within the optical head unit 3 of the optical communication terminal 1. In one possible embodiment, the optical telescope lens may be made of silicon. Silicon has a high refractive index. In fact, another advantage of using silicon is its high thermal conductivity. Furthermore, silicon's absorption properties make it an excellent long-pass filter, capable of suppressing visible wavelengths and other signals outside the transmission frequency range, thereby minimizing optical noise in the receiver system. Additionally, silicon can protect sensitive receivers and tracking sensors from thermal damage by preventing direct exposure to sunlight. Due to silicon's high thermal conductivity, temperature can be kept uniform throughout the lens body, which contains a uniform refractive index. Moreover, silicon's high refractive index allows for a short system length by maintaining a reasonable radius of curvature for the optical telescope's lens aperture.

[0032] The optical telescope lens of the optical head unit 3 is designed to extend the laser beam transmitted by the light emitting unit 2A and enter through the rear surface RSUR of the optical telescope lens. The optical telescope lens is further designed to reduce the diameter of the laser beam received through the front surface FSUR of the optical telescope lens. The reduced laser beam is then output to the light receiver unit 2B of the optical transceiver 2 through the rear surface RSUR of the optical telescope lens. The uniform material of the optical telescope lens includes absorption properties that reject optical signals, particularly visible light, with frequencies outside a predefined communication frequency range, to minimize optical noise in the light receiver unit 2B. The optical telescope lens can comprise various shapes. Possible embodiments of the optical telescope lens may include at least one rotationally symmetric cross-section having a side surface. The optical telescope lens of the optical head unit 3 may also include a conical cross-section. In a further possible embodiment, the optical telescope lens of the optical head unit 3 may also include a cylindrical cross-section.

[0033] According to the present invention, in a preferred embodiment of the optical communication terminal 1, the side surfaces of the conical cross-section of the optical telescope lens may include suppression elements suitable for suppressing optical signals of any type of backscattering or reflection. The optical telescope lens can be manufactured in a manufacturing process. The manufacturing process may include turning, grinding, or additive manufacturing.

[0034] Furthermore, in possible embodiments, the frame structure for mounting the optical transceiver 2 and / or the optical head unit 3 of the optical communication terminal 1 can be manufactured in an additive manufacturing process. For example... Figure 4 As shown in the block diagram, the optical head unit 3 may include different sub-units, including a dot-front assembly (PAA), a fine-pointing assembly (FPA), and a dichroic mirror (CBS). The dichroic mirror is designed to separate the received beam from the beam from the transmitting unit based on their respective wavelength properties.

[0035] Figure 3 A possible embodiment of an optical communication terminal 1 integrated within a frame structure is shown. In an example embodiment, the optical communication terminal 1 includes a coarse pointing assembly (CPA) 4 in front of an optical head unit 3. The optical head unit 3 is connected to an optical transceiver system 2, forming an optical transceiver. The optical transceiver 2 can also be integrated into the optical head unit 3. The optical transceiver 2 can be further connected to an electronic unit 5 of the optical communication terminal 1. The electronic unit 5 can contain various electronic components, including an FEC codec system or a terminal microcontroller (TMC). The electronic unit 5 can further include an FPA / PAA controller (FPC) and EPS and supervisory entities. Figure 3 As shown, the total length L of the optical communication terminal 1 includes the length L1 of the CPA 4, the length L2 of the optical head unit 3 and the integrated optical transceiver 2, and the length L3 of the electronic unit 5 within the frame.

[0036] Figure 4 The optical head unit 3 of the optical communication terminal 1 is described in more detail. In the example embodiment, the optical head unit 3 includes an integrated optical transmitting and receiving system 2. The optical communication terminal 1 can provide bidirectional communication, transmitting data at a high bit rate exceeding 1 Gps bidirectionally. Both the transmitting and receiving paths share the same telescope TLA. Signal separation can be achieved through polarization and signal frequency. Coarse alignment of the optical communication terminal 1 can be formed by a coarse pointing component (CPA) 4. The coarse pointing component 4 is suitable for guiding and aligning the optical beam for reception and transmission. The coarse pointing component 4 can be used to provide the basic angular motion of the laser beam required for the acquisition mode, and can also predict the relative motion between different optical communication terminals. The coarse pointing component (CPA) 4 provides a relatively large angular range. In this way, laser communication links can be established and maintained, especially with cooperating optical flight platforms, to accommodate large relative motions between two adjacent flight platforms or between a flight platform and a ground station with minimal impact on the laser beam quality. The coarse pointing component (CPA) 4 is located in front of the telescope TLA of the optical head unit 3. The telescope TLA of the optical head unit 3 is used to collect optical power and adapt to the respective laser beam diameter. According to the present invention, in the optical communication terminal 1, the telescope TLA of the optical head unit 3 includes a monolithic optical telescope lens 3A made of homogeneous material. Furthermore, the optical telescope lens 3A is transparent within its respective communication frequency range and has a high refractive index n. Figure 4 As shown, the telescope TLA can be connected to the BSACU unit 3B, which can be used as an alignment and calibration tool. Figure 4 As shown, the optical head unit 3 further includes a fine pointing assembly (FPA) 3C. The optical head unit 3 also includes a dichroic mirror (CBS) 3D. The optical head unit 3... Figure 4 An example embodiment includes a point-front component (PAA) 3E.

[0037] exist Figure 4 In an example embodiment, transceiver 2 is integrated into optical head unit 3. Transceiver 2 includes an optical transmitting unit 2A and an optical receiving unit 2B. Optical transmitting unit 2A is adapted to transmit optical communication signals within at least one predefined communication frequency range. Optical receiving unit 2B is adapted to receive optical communication signals within the predefined communication frequency range. Figure 4 In an example embodiment, the optical emitting unit 2A includes a transmitter and a modulator, an EDFA, and a transmission collimator. For example... Figure 4 As shown, the generated light signal is applied to the dichroic mirror 3D by the light emitting unit 2A through the dot front component 3E.

[0038] exist Figure 4In an example embodiment, the optical receiver unit 2B includes an optical filter for receiving optical communication signals from the dichroic mirror 3D. The optical receiver unit 2B further includes a BS beam splitter adapted to split the received beam into two signal components. The first split optical signal component is provided to the preamplifier EDFA and the RFE and demodulation unit of the optical receiver unit 2B. In the example embodiment, the second split optical signal component is provided to the four-quadrant detector (4QD). Fine pointing functionality can be provided to mitigate high-frequency interference in common optical signal paths. This interference may originate from various vibration sources on the flight platform. Furthermore, for ground communication terminals, atmospheric turbulence can be corrected.

[0039] Figure 5 A top view of the optical system within an optical communication terminal 1 is illustrated according to the present invention. As shown in the example embodiment, the telescope TLA of the optical head unit 3 includes a monolithic optical telescope lens 3A made of a uniform material. The monolithic optical telescope lens 3A of the telescope TLA is transparent within a predefined communication frequency range. Furthermore, the optical telescope lens 3A of the telescope TLA has a high refractive index n. The optical telescope lens 3A is designed to extend the laser beam transmitted by the light emitting unit 2A and enter the point front assembly 3E through the rear surface RSUR of the optical telescope lens 3A. The optical telescope lens 3A of the telescope TLA is further designed to reduce the diameter of the laser beam received through the front surface FSUR of the optical telescope lens 3A. The reduced laser beam is output through the rear surface RSUR of the optical telescope lens 3A and transmitted to the light receiver unit 2B through the dichroic mirror 3D. The optical telescope lens 3A of the telescope TLA is made in a preferred monolithic embodiment and forms a uniform object. This makes it possible for... Figure 5 The optical system shown is adaptable to mechanical vibrations or forces. Since the telescope TLA contains a monolithic optical lens, misalignment caused by mechanical forces or vibrations can be avoided. Furthermore, the optical system using a monolithic optical telescope lens 3A eliminates the need for complex interactions between different components (such as different lenses or mirrors), thereby reducing complexity and improving the adaptability and robustness of the optical system. Therefore, the optical system with the monolithic optical telescope lens 3A does indeed operate more reliably because misalignment or failure of different optical components is impossible. Moreover, using a monolithic optical telescope lens 3A allows for a reduction in the size of the optical system, thereby reducing the size of the optical head unit 3. In this way, the length and overall size of the optical communication terminal 1 can be minimized, thus saving transportation space. Figure 5As shown, the optical telescope lens 3A of the telescope TLA includes a front surface FSUR and a rear surface RSUR. In a preferred embodiment, the front surface FSUR of the optical telescope lens 3A includes an aspherical convex front surface. The rear surface RSUR is a concave surface. The concave rear surface RSUR may include a spherical concave rear surface or an aspherical concave rear surface. The optical telescope lens 3A extends the laser beam transmitted by the light emitter unit 2A, which enters through the rear surface RSUR of the optical telescope lens 3A, and is also designed to reduce the laser beam diameter when received through the front surface FSUR. The reduced laser beam is then output through the rear surface RSUR of the optical telescope lens 3A and supplied to the light receiver unit 2B. Figure 5 As shown in the embodiments, the uniform material of the optical telescope lens 3A may contain absorption properties that suppress optical signals with frequencies outside the predefined communication frequency range in order to minimize any type of optical noise in the optical receiver unit 2B.

[0040] like Figure 5 As shown in the embodiments, the optical telescope lens 3A of the telescope TLA may include at least one rotationally symmetric section having a side surface surrounding it. Figure 5 In the example embodiment, the optical telescope lens 3A includes a tapered cross-section. The optical telescope lens 3A may also include other shapes and forms, such as... Figure 11A , 11B As explained in 11C, the tapered portion of the optical telescope lens 3A, in the preferred embodiment, includes suppression elements for suppressing backscattering or reflection of optical signals.

[0041] Figure 6A The conical design of the optical telescope lens 3A is explained, which incorporates some suppression elements to suppress backscattered or reflected optical signals. Figure 6A The front and side views of the optical telescope lens 3A, as well as the perspective rear view, are shown.

[0042] Figure 6B This illustration shows a further possible example embodiment of an optical telescope lens 3A that can be used in an optical communication terminal 1 according to the present invention. Figure 6A In its implementation, the number N of suppression elements may vary depending on the application and the size of the lens. In an example embodiment, the optical telescope lens includes three suppression elements (N=3) 6-1, 6-2, and 6-3, suitable for suppressing backscattered or reflected optical signals. The front surface FSUR of the optical telescope lens 3A includes an aspherical convex front surface.

[0043] Figure 6B Another possible exemplary embodiment of the optical telescope lens 3A is shown, which has not only a conical cross section but also a cylindrical cross section. Figure 6BThe side surface of the tapered portion of the optical telescope lens 3A may also include a suppression element to suppress backscattered or reflected optical signals. The size and length of different portions of the optical telescope lens 3A may vary depending on the application.

[0044] Figure 7 The image shows a cross-section of an optical system with a coarse pointing component (CPA) at the front. In an example embodiment, the coarse pointing component (CPA) includes an X / Y dot system comprising a so-called Risley prism pair.

[0045] Figure 8 Another top view shows an optical system implemented in the optical head unit 3 of an optical communication terminal 1 according to the present invention. In an example embodiment, the optical receiver unit 2B may include a monolithic optical filter and a beam splitter lens 7 adapted to provide the received optical signal to the tracking sensor 8 of the optical transceiver 2. The optical filter and beam splitter lens 7 may also be assembled from different components that can be glued together. It may include a first lens 7A, a folding mirror prism 7B, a lens 7C, and a beam splitter cube 7D.

[0046] Figure 9 Different views of possible implementations of the optical filter and beamsplitter lens 7 are shown. The telescope TLA of the opto-head unit 3 is adapted to receive incoming communication signals and distribute the received power to the tracking and data sensors 8. The optical filter and beamsplitter lens 7 can be implemented as a single component, such as the lens and the beamsplitter. In this way, the assembly and integration work can be reduced by further minimizing the number of components required within the optical system of the optical communication terminal 1.

[0047] Figure 10 Different views are shown of the frame structure of the optical transceiver unit 3, which mounts the optical transceiver 2 and / or the optical communication terminal 1. In the preferred embodiment, as Figure 10 The frame structure 9 shown can be manufactured using additive manufacturing processes. For example... Figure 10 As shown, the frame structure 9 can fix the CPA 4 in front of the electronic unit 5 of the optical head unit 3 and the optical communication terminal 1. Accordingly, the optical head unit 3 may include a dot-front assembly (PAA), a fine pointing assembly (FPA), and a dichroic mirror (CBS).

[0048] Figure 11A , 11B Figures 11C and 11C show cross-sections of different example embodiments of the optical telescope lens 3A used in the optical system of the optical communication terminal 1.

[0049] Figure 11AThe image shows an optical telescope lens 3A with only one conical cross-section, which, in a possible implementation, may include a side surface that may include a predetermined number N of suppression elements.

[0050] Figure 11B This describes a possible embodiment of the optical telescope lens 3A, which consists of a conical cross section and a cylindrical cross section.

[0051] Figure 11C A further example embodiment of the optical telescope lens 3A, consisting only of a cylindrical portion, is shown. (See example...) Figure 11A , 11B As shown in 11C, in any case, the optical telescope lens 3A includes a convex front surface FSUR and a concave back surface RSUR.

[0052] The optical telescope lens 3A can be made of different materials. In a preferred embodiment, the optical telescope lens 3A is made of silicon. Silicon has absorption properties that suppress light signals with frequencies outside a predefined communication frequency range. For example, the predefined communication frequency range could be an infrared frequency range or band. In this way, optical noise in the optical receiver unit 2B is minimized. The communication frequency range or communication band may include one or more communication channels CH that transmit data in the same or opposite transmission directions.

[0053] Silicon (Si) has a relatively high refractive index (n). Another advantage of using silicon is its high thermal conductivity. In one alternative embodiment, the optical telescope lens 3A of the telescope can be made of germanium (Ge). In another alternative embodiment, the optical telescope lens 3A of the telescope TLA can also be made of glass. In the preferred embodiment, the optical telescope lens 3A is composed of a monolithic piece of homogeneous material.

Claims

1. An optical communication terminal for optical communication using a laser beam to transmit optical communication signals, the optical communication terminal (1) comprising: An optical transceiver (2) having an optical transmitting unit (2A) adapted to transmit optical communication signals within at least one predefined communication frequency range and an optical receiving unit (2B) adapted to receive optical communication signals within the predefined communication frequency range; and The optical head unit (3) has a telescope (TLA) for collecting optical power and adapting to the diameter of the laser beam, wherein the telescope (TLA) consists of a monolithic optical telescope lens (3A) made of a homogeneous material, is transparent in the communication frequency range, and has a high refractive index n.

2. The optical communication terminal according to claim 1, wherein the optical telescope lens (3A) of the telescope (TLA) includes an aspherical convex front surface (FSUR) and a spherical or aspherical concave back surface (RSUR).

3. The optical communication terminal according to claim 1 or 2, wherein the optical telescope lens (3A) is designed to extend the laser beam transmitted by the optical emitting unit (2) and enter through the rear surface (RSUR) of the optical telescope lens (3A), and is also designed to reduce the diameter of the laser beam received through the front surface (FSUR) of the optical telescope lens (3A), wherein, The reduced laser beam is output to the optical receiver unit (2B) through the rear surface (RSUR) of the optical telescope lens (3A).

4. The optical communication terminal according to claim 1, wherein the uniform material of the optical telescope lens (3A) has high thermal conductivity.

5. The optical communication terminal according to claim 1, wherein the uniform material of the optical telescope lens (3A) includes absorption characteristics that suppress optical signals whose frequencies exceed a predefined communication frequency range, the optical signals being visible light, to minimize optical noise in the optical receiver unit (2B).

6. The optical communication terminal according to claim 1, wherein the optical telescope lens (3A) includes at least one rotationally symmetric cross section having a surrounding side surface.

7. The optical communication terminal according to claim 6, wherein the optical telescope lens comprises a conical cross-section and / or a cylindrical cross-section.

8. The optical communication terminal according to claim 7, wherein, The side surface of the conical cross-section of the optical telescope lens (3A) includes N suppression elements, which are used to suppress backscattered or reflected light signals.

9. The optical communication terminal according to claim 1, wherein the uniform material of the optical telescope lens (3A) is made of silicon or germanium.

10. The optical communication terminal according to claim 1, wherein the optical telescope lens (3A) is manufactured in a turning process, a grinding process or an additive manufacturing process.

11. The optical communication terminal according to claim 1, wherein the optical receiver unit (2B) includes a monolithic optical filter and a beam splitter lens (7) to provide the received optical signal to at least one tracking sensor (8) of the optical transceiver (2).

12. The optical communication terminal according to claim 1, wherein the aspherical convex surface of the optical telescope lens (3A) is adapted to receive a laser beam from the coarse pointing component (4) of the optical communication terminal (1).

13. The optical communication terminal according to claim 1, wherein the frame structure (9) for mounting the optical transceiver (2) and / or the optical head unit (3) of the optical communication terminal (1) is manufactured in an additive manufacturing process.

14. The optical communication terminal according to claim 1, wherein the optical head unit (3) includes a front-point assembly (PAA), a pointing assembly (FPA), and a dichroic mirror (CBS), wherein the dichroic mirror is designed to separate the received light beam and the light beam from the transmitting unit by their respective wavelength properties.

15. The optical communication terminal according to claim 1, wherein the optical communication terminal (1) is integrated into a high-altitude platform, an aircraft or drone or other mobile flight station, or may be integrated into a ground station to provide tower-to-tower communication.

16. An optical head unit (3) of an optical communication terminal (1), the optical head unit (3) having a telescope (TLA) provided for acquiring optical power and adapting to the laser beam diameter, The telescope (TLA) consists of a monolithic optical telescope lens (3A) made of a uniform material, is transparent within the communication frequency range of the optical communication terminal (1), and has a high refractive index n.

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