Signal transmission in an imaging system

Abstract

Transmitter (11, 21) and receiver (12, 22) for an imaging system for transmitting signals and imaging system, wherein the transmitter (11, 21) comprises a light wave generator (3) and is configured to modulate the signals onto generated light waves (4) and to transmit them with the light waves (4, 6), wherein the transmitter (11, 21) comprises a fanning optic configured to fan the generated light waves (4, 6) in a plane, wherein the receiver (12, 22) comprises a light guide optic and a light detector (9), wherein the light guide optic is configured to direct light arriving from an angular range in a light entry plane to the light detector (9) for each angle of the angular range.

Description

[0001] The invention relates to a transmitter for an imaging system, a receiver for an imaging system, an imaging system and a use of fanned-out light waves for signal transmission in an imaging system.

[0002] Regardless of the grammatical gender of a particular term, it includes persons with male, female or other gender identities.

[0003] Medical imaging systems with rotating data acquisition components often face the problem that providing a data connection is difficult due to the rotation. For example, in computed tomography (CT) systems, considerable amounts of data acquired by an X-ray detector must often be transferred to an image processing computer. To ensure real-time requirements for error handling and to transfer the data in a finite time, high transmission bandwidths, for example in the range of several gigabits per second, are necessary. During scanning in a typical third-generation CT system, the detector rotates at high speed around an isocenter containing the object to be scanned.The transfer of data can be particularly problematic due to rapid rotation, a large amount of data and the fact that data transfer via the center of rotation is usually not an option due to the object being scanned there.

[0004] In the current state of the art, transmission is sometimes achieved through direct contact, for example, using slip rings, or through radio transmission, particularly high-frequency or similar methods. However, these solutions sometimes have problems with interference, especially at higher transmission rates. Furthermore, the necessary setup is often complex and expensive. Radio signals can also potentially pose problems with electromagnetic compatibility (EMC) with other devices.

[0005] It is therefore an object of the present invention to provide an alternative possibility for data transmission in an imaging system, which preferably at least partially improves the above-mentioned problems.

[0006] This object is achieved by a transmitter according to claim 1, a receiver according to claim 4, an imaging system according to claim 12 and a use according to claim 15. Further features and advantages emerge from the dependent claims, the description and the attached figures.

[0007] According to a first aspect of the invention, a transmitter for an imaging system, in particular a computed tomography system, is provided for transmitting signals, in particular comprising data. The transmitter comprises a lightwave generator and is configured to modulate the signals onto generated lightwaves and transmit them with the lightwaves. The transmitter comprises a fan-out optics configured to fan out the generated lightwaves in a plane. Advantageously, the transmitter can be used for contactless signal transmission and can be implemented with a relatively simple structure.

[0008] The transmitter is particularly designed to be used in or for an imaging system. The imaging system can, in particular, be a medical imaging system. The imaging system can, for example, be a computed tomography system. The transmitter can be designed to be attached to a rotatable part or a rotatable component of an imaging system.

[0009] When a rotating part is mentioned in the context of this invention, it can fundamentally include any rotating part. In particular, the rotating part can be a rotating component. The rotatable part can, for example, be a rotatable gantry of a computed tomography system. Alternatively or additionally, the transmitter can be designed to be attached to and / or connected to a stationary part or a stationary component. The transmitter can comprise a connection, in particular a data connection. It can be provided that a receiver is arranged on the other of the stationary and rotatable parts. The connection can be designed so that the transmitter can be connected to the rotatable part and / or the stationary part.

[0010] The transmitter is configured to transmit signals. The signals may, for example, comprise data signals. The data signals may comprise image data and / or detector data. For example, the data signals may comprise data recorded by a detector on a rotatable part. The signals may comprise control command signals. For example, control commands may be sent via the transmitter to a rotating part of the imaging system, or vice versa.

[0011] The transmitter comprises a lightwave generator. The lightwave generator can also be referred to as a lightwave source. The terms lightwave generator and light are to be understood broadly within the scope of this invention. The lightwave generator can generally be any device that is suitable for generating lightwaves within the scope of this invention and can be installed in the imaging system. For example, the lightwave generator can be a laser or comprise a laser. In general, light can comprise electromagnetic radiation in the visible range. Light can also comprise light in the ultraviolet range. Light can also comprise light in the infrared range. For example, light can be provided in the wavelength range from 500 nm to 1200 nm, preferably 800 nm to 1000 nm.

[0012] The transmitter is configured to modulate the signals onto light waves, particularly those generated by the light wave generator, and to transmit them along with the light waves. Light waves can be a good way to transmit signals, especially data, without contact. Light waves can have the advantage of good electromagnetic compatibility with other signals or devices that occur in the vicinity of an imaging system. Their use can be particularly advantageous for medical imaging systems because potential interference factors relevant to signal transmission via light, such as dust, smoke, vapor, etc., typically found in the medical field, do not occur anyway, precisely due to hygiene requirements. Compared to Wi-Fi or radio transmission, signal transmission via light can have the advantage of enabling a relatively sharp and flat signal.In addition, it can be relatively easy to attenuate light to limit signal propagation beyond the receiver if necessary. In particular, attenuation can also be concentrated on a specific wavelength range, especially the wavelength range of the light source.

[0013] The transmitter further comprises a fan-out optic designed to fan out the generated light waves in a plane. In principle, the term "fan-out optic" is to be understood broadly within the scope of this invention. It can comprise any device suitable for fanning out a light beam. Preferably, the fan-out optic is designed to fan out the light wave in a plane. In particular, the fan-out optic can be designed to generate a flat light fan. "Flat" can be understood to mean that the light fan is not significantly wider in a direction perpendicular to its fan surface than the original light wave before fanning out. Preferably, the transmitter and / or the fan-out optic can be designed to fan out the light wave in a plane of rotation. The plane of rotation can in particular be the plane of rotation of the rotatable part.The fan-out optics can be designed to create a light cone from the light wave. Fanning out the light wave has the advantage that the light can still reach a receiver over a larger range of rotation angles. In contrast, a thin light beam would only hit the receiver briefly during a rotation of either the transmitter or the receiver. This could mean, for example, that a signal can only be transmitted for a short time during a rotation or that the alignment of the transmitter and / or receiver would have to be constantly readjusted. With a fan-out light wave, on the other hand, a receiver can be reached over a larger range of rotation angles.

[0014] According to one embodiment, the fan-out optics comprises a line generator lens and / or a Powell lens. An alternative possibility could, for example, be a mirror that is rapidly rotated back and forth over an angular range or moved in a circular motion. In contrast, however, a line generator lens can represent a particularly simple and mechanically less demanding way of fanning out the light wave. A Powell lens can be a particularly suitable and easily implemented way of fanning out the beam path of the light wave. The lens, in particular the line generator lens and / or the Powell lens, can optionally comprise side walls with light traps. The light traps can be designed to absorb light or deflect it in a specific direction. The specific direction can, in particular, be a different direction than the direction in which the light fan is directed.Light traps can be advantageously helpful for improving the signal by preventing or reducing the interference of modal dispersion within the lens with the main signal. In other words, this ensures that only the correct rays reach the receiver. The correct rays can, in particular, be the main rays that have not been additionally reflected by side walls, for example.

[0015] According to one embodiment, the transmitter is designed to generate, in particular simultaneously, different light waves with different wavelengths. The transmitter can be designed to modulate a signal onto each light wave. The transmitter can be designed to fan out each of the light waves. For example, multiple light sources, such as laser sources, with different wavelengths can be integrated into the transmitter. Advantageously, this embodiment allows multiple signals to be generated simultaneously and transmitted as needed. This allows a data rate to be increased. Differentiation of the signals can be provided based on the wavelengths used. The wavelengths can be designed to be easily distinguishable. For example, the wavelengths cannot be multiples of one another. Advantageously, a higher data rate can thus be achieved.

[0016] Another aspect of the invention is a receiver for an imaging system for receiving signals modulated onto fanned-out light waves, wherein the receiver comprises a light guide optic and a light detector, wherein the light guide optic is configured to guide light arriving from an angular range in a light entry plane to the light detector for each angle of the angular range. The advantages and features of the transmitter can be transferred analogously to the receiver and vice versa.

[0017] Like the transmitter, the receiver is particularly designed to be used in or for an imaging system. The receiver can be designed to be attached and / or connected to a rotatable part or a rotatable component of an imaging system. Alternatively or additionally, the receiver can be designed to be attached and / or connected to a stationary part or a stationary component. The receiver can comprise a connection, in particular a data connection. The connection can be designed so that the receiver can be connected to the rotatable part and / or the stationary part. The connection can be designed to forward received data.

[0018] Analogous to the fan-out optics of the transmitter according to the invention, the receiver is designed to receive signals modulated onto fan-out light waves. The signals can comprise, for example, data signals. The data signals can comprise image data and / or detector data. The signals can comprise control command signals. For example, the receiver can be designed to receive control commands and forward them. For example, the control commands for a detector can be provided to a rotating part of the imaging system.

[0019] The receiver comprises a light guide optic and a light detector. The light detector can be configured to quickly detect when a signal arrives and to begin recording the signal. The light guide optic can be used to transmit light waves, in particular light waves with modulated signals, to the light detector. By advantageously designing the light guide optic to guide light arriving from an angular range in a light entry plane to the light detector for each angle of the angular range, the time window in which light waves can be transmitted from a transmitter to the receiver can advantageously be increased in a setup with a rotating part and a stationary part of an imaging system. By detecting an angular range, the receiver can cooperate particularly well with the transmitter according to the invention if the transmitter generates fanned-out light waves.Together, the transmitter and receiver can thus transmit signals from or to a rotating part, for example over a larger rotation range of a rotating part. The light-guiding optics can, in particular, guide fanned-out light over the angular range to the light detector. The light-guiding optics can comprise at least one mirror. The at least one mirror can be arranged such that light arriving from the angular range is reflected to the light detector. Optionally, the at least one mirror can be concave. Optionally, the at least one mirror can be adjustable, in particular automatically adjustable. For example, the receiver can be designed to automatically adapt an orientation of the mirror to a rotational position of a rotating part of an imaging system.

[0020] Optionally, the receiver can include a converging lens. The converging lens can be arranged, in particular, between the light-guiding optics and the light detector. The converging lens can be designed to focus light waves arriving from the light-guiding optics onto the light detector. The converging lens can be placed at a light input of the light detector and / or attached to the light detector.

[0021] According to one embodiment, the light-guiding optics comprises a conical mirror. With a conical mirror, light can advantageously be guided from one plane, i.e. in particular the plane in which a light wave is fanned out, to the light detector. Preferably, a tip of the conical mirror can be directed towards the light detector. Preferably, the axis of the conical mirror can be aligned perpendicular to an extension of the angular range. This can enable a particularly simple and efficient configuration of the conical mirror and light detector. However, other configurations are also conceivable. Preferably, a light input of the light detector can have a diameter that is at least as large as the diameter of the conical mirror at the level of the angular range.Advantageously, a conical mirror can achieve an at least approximately constant light path without the need to adjust the mirror when the transmitter or receiver rotates. It has also been shown that a configuration with a conical mirror can have relatively low susceptibility to vibrations.

[0022] According to one embodiment, the angular range extends over at least 15°, preferably at least 45°, more preferably at least 90°, most preferably at least 150°. An extension of at least 15° can make it possible to detect part of a fanned-out light wave from several directions of rotation, which already represents an improvement over a detector that has to be aligned directly to the signal source, i.e. the transmitter. A larger angular range can be even more advantageous in that a signal can be detected for even more rotational positions. It can also be advantageous if the angular range extends over a full 360°, for example. This can be particularly desirable if a signal is to be transmitted continuously from a transmitter to the receiver.However, especially when using multiple transmitters and / or receivers, this may not be necessary, and an angular range of at least 150° can be sufficient to ensure the best possible signal transmission. This can be the case, for example, if the receiver is intended to always receive signals when it is positioned relatively close to the transmitter in terms of rotation. If the receiver is somewhat further away from the transmitter, the signal can be transmitted, for example, via a different receiver or from another transmitter that is now positioned closer to the receiver. In some configurations, it can also be advantageous if the angular range is at least 180° or essentially 180°. It can be provided that the angular range is less than 200°.This can be advantageous, for example, to block interference signals coming from a direction from which no real signal is expected anyway.

[0023] According to one embodiment, the receiver comprises a housing with a light inlet, wherein the light inlet is designed to allow light entry according to the angular range, wherein the light guide optics and the light detector are arranged in the housing. The housing can, for example, enable dust protection of the light guide optics and / or the light detector. The housing can be designed to block incoming stray light. Stray light can, for example, be reflected light from a transmitter or light from another, e.g. external, light source. In particular, the housing can be designed to block light that arrives from a direction other than the angular range. The housing can be designed to be opaque beyond the light inlet. The housing can be coated with a light-attenuating or light-absorbing material.Light-absorbing in the context of this invention can preferably mean that at least 95%, preferably at least 98%, particularly preferably at least 99%, of the incident light, at least in the visible and / or light wave spectrum, is absorbed.

[0024] According to one embodiment, the housing comprises a light-absorbing inner wall at least in an area around the light detector. For example, the inner wall can be provided with a light-absorbing coating. A light-absorbing inner wall can prevent or reduce the reflection of scattered radiation and / or other unwanted radiation. For example, light rays that would not strike a converging lens in front of the light detector with sufficient centering can be eliminated by the light-absorbing inner wall. The light-absorbing inner wall can prevent mode dispersion.

[0025] In principle, modal dispersion can arise, in particular, when individual modes propagate along different paths. These different paths, possibly depending on the refractive index of the optics used, can result in different propagation times for the various radiation paths. During signal transmission, this can, for example, lead to deformation and superposition of the signal modulated onto the light waves. This can degrade signal quality. Reflections from sidewalls can cause signal blurring due to strong modal dispersion in a temporal context. A light-absorbing inner wall can advantageously reduce reflections and thus modal dispersion. This can lead to improved signal quality.For example, 0.1 ns bit light pulses can correspond to a path length of approximately 3 cm per bit until the next bit is emitted (at a speed of light of approximately 300 million m / s). Assuming a total light path length of 2 meters, for example, approximately 67 bits are traveling simultaneously. Avoiding reflections can therefore be particularly advantageous, for example to prevent localized signal cancellation due to negative interference. This problem can be addressed, for example, additionally or alternatively, by providing at least two light detectors that simultaneously detect signals from the same transmitter. The at least two light detectors can be provided so that a comparison of the signals detected by the at least two light detectors is used to correct the signals.

[0026] According to one embodiment, the light-absorbing inner wall also extends to an area behind the light-guiding optics opposite the light input. This advantageously prevents or at least reduces back reflection from the rear inner wall toward the light-guiding optics. In particular, it can be provided that light waves emitted by a transmitter essentially only come from one side due to the circular motion of a rotating part before the receiver is no longer in the beam path of the fanned-out light wave. Thus, the light-absorbing inner wall can be used behind the light-guiding optics without interfering with the actual signal acquisition. Optionally, it can also be used to prevent unwanted external light influences from the rear.

[0027] According to one embodiment, the light inlet of the housing in the angular range is designed as a transparent cylindrical section. Transparent is to be understood in particular to mean that the transparent cylindrical section is permeable to at least one used light wavelength. The used light wavelength can correspond to the light wavelength for which the light detector is designed or sensitive. In particular, an axis of the cylinder can run essentially parallel to the axis of the conical mirror. The cylinder axis can essentially coincide with the cylinder axis of the conical mirror. A transparent cylindrical section as an inlet can prevent dust and dirt from entering the housing and at the same time ensure light transmission. A cylindrical shape can also enable light rays directed at the conical mirror to pass essentially perpendicularly through the wall of the cylinder.This can prevent or minimize deflection of the light.

[0028] According to one embodiment, the receiver comprises a parabolic mirror designed to deflect light beams onto the light detector, wherein the light detector is arranged between the light-guiding optics and the parabolic mirror. A parabolic mirror can increase the number of beams reaching the light detector. This can, for example, increase the efficiency of the detector. This embodiment can be advantageous, for example, when only a low signal strength reaches the receiver. For example, this can be the case with a relatively weak transmitter and / or a transmitter that is relatively far away from the receiver and / or a transmitter that spreads the light wave particularly widely.

[0029] According to one embodiment, the receiver is configured to break down incoming light waves of different wavelengths. For example, the light detector can be configured to distinguish between different wavelengths. Alternatively, the receiver can comprise multiple light detectors. For example, the light guide optics can be configured to guide incoming light to the multiple light detectors. With this embodiment, the receiver can advantageously be capable of receiving different signals or data streams simultaneously.

[0030] A further aspect of the invention is an imaging system with a rotatable component and with a stationary component. A stationary component is in particular a component that is not rotated during normal operation or that is stationary during normal operation. The imaging system comprises at least one transmitter as described herein and at least one receiver for receiving signals modulated onto fanned-out light waves. The at least one transmitter is arranged on the rotatable component and the at least one receiver is arranged on the stationary component such that the at least one transmitter is at least temporarily aligned during rotation of the rotatable component such that light waves can be transmitted from the at least one transmitter towards the at least one receiver and received by the at least one receiver.Additionally or alternatively, the at least one receiver is arranged on the rotatable component and the at least one transmitter is arranged on the stationary component, such that the at least one transmitter is at least temporarily aligned during a rotation of the rotatable component such that light waves can be sent from the at least one transmitter in the direction of the at least one receiver and received by the at least one receiver. The at least one receiver can in particular be at least one receiver as described herein. The imaging system can in particular be a medical imaging system. The imaging system can, for example, be a computed tomography system with a rotatable gantry. The rotatable gantry can be the rotatable component. The stationary component can, for example, be a holding frame around the rotatable gantry.Depending on the design, signals can be sent from the stationary component to the rotatable component or vice versa, or both simultaneously. For example, detector data can be transmitted from a detector on the rotatable component to the stationary component, and command signals can be transmitted from the stationary component to the rotatable component. The command signals can be provided, for example, for the detector. The command signals can be provided, for example, for a rotatable X-ray source of a computed tomography system. All advantages and features of the transmitter and receiver can be transferred analogously to the imaging system, and vice versa.

[0031] The system with the transmitter and receiver according to the invention can be particularly advantageous for a computed tomography system. On the one hand, a computed tomography system often has large amounts of data that must be transmitted from a rotating detector. On the other hand, the gantry typically rotates only in one plane, which can make it particularly easy to fan out a light wave.

[0032] The rotatable component and the stationary component can be arranged within a common outer shell. The outer shell can preferably be opaque. The outer shell can be designed to keep out dirt particles, in particular dust, smoke, and / or vapor. The outer shell can be, for example, the outer shell of a computed tomography gantry.

[0033] The transmitter and receiver can preferably be aligned such that the angular range of the receiver lies in the plane into which the light wave is fanned out. For example, the axis of a conical mirror of the receiver can be aligned substantially parallel to a normal of the plane into which the light wave is fanned out.

[0034] The transmitter and receiver can be synchronized with each other, so that the receiver automatically becomes active as soon as the transmitter is in a transmitting position relative to the receiver. Alternatively or additionally, the receiver can be configured to automatically start signal acquisition as soon as a light wave arrives at the receiver.

[0035] According to one embodiment, the imaging system comprises a plurality of transmitters on the rotatable component and / or a plurality of receivers on the stationary component, which are arranged such that a temporally seamless signal transmission of a signal is possible upon rotation of the rotatable component. Alternatively or additionally, the imaging system comprises a plurality of receivers on the rotatable component and / or a plurality of transmitters on the stationary component, which are arranged such that a temporally seamless signal transmission of a signal is possible upon rotation of the rotatable component. Advantageously, with a plurality of transmitters and / or a plurality of receivers, it can be achieved that the distances between respectively active transmitters and receivers are kept short during rotation of the rotatable components.The transmitters and receivers can be configured in such a way that signal transmission always takes place via those transmitters and receivers which are not exceeding a maximum set distance from one another. It can be provided that during the rotation, depending on the position, one transmitter continues to send a signal after another transmitter, and / or that during the rotation, depending on the position, one receiver continues to receive a signal after another receiver. It can be provided that when transitioning from one transmitter to the next transmitter and / or from one receiver to the next receiver, an overlap is provided during which both transmitters send a signal and / or both receivers receive a signal. An overlap can create redundancy which enables the receivers to synchronise to the new signal.Synchronization may involve detecting the correct signal and / or sorting it into a correct encoding.

[0036] According to one embodiment, the imaging system is designed to send a plurality of light waves, each with different frequencies and at least one signal, simultaneously from the at least one transmitter to the at least one receiver. Advantageously, larger amounts of data can thus be transmitted simultaneously. For example, at least one transmitter can be designed to generate a plurality of light waves with different frequencies. Alternatively or additionally, a plurality of different transmitters can be provided, each of which can generate light waves at different frequencies. For example, at least one receiver can be designed to receive a plurality of frequencies and to be able to differentiate between them. For example, a plurality of receivers can be provided that can receive at different frequencies.

[0037] A further aspect of the invention is the use of fanned-out light waves for signal transmission in an imaging system with a rotatable component, in particular a computed tomography system with a rotatable gantry. All advantages and features of the transmitter, receiver, and imaging system can be applied analogously to the application, and vice versa.

[0038] Another aspect of the invention is a method for signal transmission in an imaging system having a rotatable component, wherein the signal is sent from a rotating component to a stationary component or vice versa, the method comprising the following steps: - Modulating the signal onto a light wave and transmitting the light wave; - fanning out of the light wave; - Detecting the light wave with a receiver.

[0039] The system used in the method can, in particular, be a medical imaging system. The system used in the method can, in particular, be a computed tomography system. All advantages and features of the transmitter, the receiver, the imaging system, and the use can be transferred analogously to the method, and vice versa. The generation and emission of the light wave can, in particular, be provided with a transmitter as described herein. The detection of the light wave can, in particular, be provided with a receiver as described herein. For example, the light wave can be fanned out using a Powell lens. For example, the receiver can comprise a light-guiding optic comprising at least one conical mirror, which guides the light wave or a portion of the light wave to a light detector.

[0040] A further aspect of the invention is a computer program product comprising instructions which, when the program is executed by an imaging system having a transmitter and a receiver as described herein, cause the imaging system to carry out the steps of the method as described herein. All advantages and features of the method and the other aspects of the invention can be transferred analogously to the computer program product and vice versa. The computer program product can be stored, for example, on a computer-readable storage medium, in particular a non-volatile storage medium. The storage medium can be, for example, a hard disk, an SSD, a flash memory, an online server, etc.

[0041] All embodiments described herein can be combined with one another unless explicitly stated otherwise.

[0042] Embodiments are described below with reference to the attached figures. Fig. 1 shows a schematic cross section of an imaging system, namely a computed tomography system, according to an embodiment of the invention, Fig. Figure 2 shows a cross-section from the side of a transmitter for transmitting signals according to an embodiment of the invention, Fig. 3 shows a sectional view from above of a receiver according to an embodiment of the invention, Fig. 4 shows a sectional view from the side of a receiver according to the Fig. 3 shown embodiment of the invention, Fig. 5 shows a sectional side view of a receiver according to another embodiment of the invention, Fig. 6 shows a schematic functional diagram of an imaging system with two stationary transmitters and four receivers on a rotatable component according to an embodiment of the invention, Fig. 7 shows a schematic functional diagram of an imaging system with two transmitters on a rotatable part and four stationary receivers according to an embodiment of the invention, and Fig. 8 shows a flowchart of a method for signal transmission in an imaging system with a rotatable component according to an embodiment of the invention.

[0043] Fig. 1 shows a schematic cross-section of a computed tomography system according to an embodiment of the invention. The computed tomography system has a rotatable component 1 and a stationary component 2. The rotatable component 1 is a rotatable gantry with detectors (not shown here), the detector data of which can be transmitted to receivers 22 on the stationary component 2 by means of a transmitter 11 arranged on the rotatable component 1. During a rotation of the rotatable component 1, the transmitter 11 on the rotatable component 1 is at least temporarily aligned such that light waves can be transmitted from the transmitter 11 toward at least one of the receivers 22 on the stationary component 2 and received by the respective receiver 22. Furthermore, in this embodiment, several receivers 12 are arranged on the rotatable component 1 and a transmitter 21 is arranged on the stationary component 2.During a rotation of the rotatable component 1, the transmitter 21 on the stationary component 2 is at least temporarily aligned relative to the receivers 12 on the rotatable component 1 such that light waves can be transmitted from the transmitter 21 in the direction of at least one of the receivers 12 and received by the respective receiver 12. For example, command data can be transmitted from the stationary component 2 to the rotatable component 1. Preferably, with appropriately widely spread light waves emitted by the transmitters 11, 21, a temporally seamless signal transmission of a signal can be achieved during a rotation of the rotatable component 1, in that at least one receiver 12, 22 is always within the transmission range of the respective transmitter 21, 11. It can optionally be provided to provide additional transmitters 11, 21 and / or additional receivers 12, 22 in order to ensure better coverage.The transmitters 11, 21 and receivers 12, 22 can, for example, transmit the signal contained in the . Fig. 2 to 5, respectively. The computed tomography system can optionally be configured to transmit multiple light waves, each with different frequencies and at least one signal simultaneously, from one of the transmitters 11 to the receivers 22. Alternatively, different light waves of different frequencies could also be generated with additional transmitters and detected with additional receivers.

[0044] Fig. 2 shows a cross-section from the side of a transmitter 11, 21 for transmitting signals according to an embodiment of the invention. The transmitter 11, 21 comprises a lightwave generator 3 and is configured to modulate the signals onto generated lightwaves 4 and transmit them with the lightwaves. The transmitter 11, 21 further comprises a fan-out optic in the form of a Powell lens 5, which is configured to fan out the generated lightwaves 4 in a plane to generate fanned-out lightwaves 6. Optionally, the transmitter 11, 21 can be configured to generate different lightwaves 4, 6 with different wavelengths. This allows more signals to be transmitted simultaneously or with a smaller time offset and deconstructed by a detector.

[0045] Fig. Figure 3 shows a sectional view from above of a receiver 12, 22 according to an embodiment of the invention. The receiver 12, 22 comprises a light guide optic in the form of a conical mirror 7 and a light detector 9 (in this illustration in Fig. 3 not visible). The conical mirror 7 is designed and oriented in such a way that it guides light arriving from an angular range in a light entry plane to the light detector 9 for each angle of the angular range. The light entry plane here essentially corresponds to the image plane shown in Fig. 3. The angular range in this embodiment is approximately 180° and is limited by a housing wall 8 of a housing. The area not covered by the housing wall 8 corresponds to a light input 10 of the receiver 12, 22. The redirection of the incoming light wave 6 is shown in the illustration of Fig. 4 clearly visible.

[0046] Fig. 4 shows a sectional view from the side of a receiver 12, 22 according to the Fig. 3. The drawn beam path of the light wave 6 shows the path of the light which is guided from the conical mirror 7 to the light detector 9. Due to the conical shape of the conical mirror 7, the light can be guided onto the light detector 9 from different directions depending on the angular range. The housing wall 8 is preferably designed to be light-absorbing. For example, the housing wall 8 can be coated on the inside with a light-absorbing material. This can prevent unwanted reflections. The light-absorbing housing wall 8 also extends to an area behind the conical mirror 7 opposite the light inlet 10. The light inlet 10 of the housing is designed as a transparent cylindrical section, i.e., one permeable to the light wave, in the angular range. A cylindrical axis of the cylinder runs essentially parallel to the axis of the conical mirror 7.It can also be seen that the conical mirror 7 and the light detector 9 are arranged in the housing, ie within the housing walls 8.

[0047] Fig. Figure 5 shows a sectional side view of a receiver 12, 22 according to another embodiment of the invention. The receiver 12, 22 in this embodiment differs from the one shown in Fig. 4 is particularly distinguished by the provision of a parabolic mirror 90. The parabolic mirror 90 is designed to deflect light rays 6 onto the light detector 9. For this purpose, the parabolic mirror 90 is arranged behind the light detector 9, as seen from the conical mirror 7. In other words, the light detector 9 is arranged between the conical mirror 7 and the parabolic mirror 90. The parabolic mirror 90 can increase the light intensity striking the light detector 9. This embodiment further differs in that there is no coated rear wall 8 provided behind the conical mirror 7. Instead, a 360° beam entrance of the receiver 12, 22 is provided. This allows light waves to be received from all directions. The receiver 12, 22 can therefore enable greater coverage.This is also particularly advantageous in combination with the parabolic mirror 90, because even signals coming from further away can be amplified and arrive at the light detector 9 through the parabolic mirror 90. For example, it can be provided that the receiver 12, 22 continuously receives signals from a transmitter 11, 21 that rotates relative to the receiver 12, 22.

[0048] Fig. Figure 6 shows a schematic functional diagram of an imaging system with two stationary transmitters 21 and four receivers 12 on a rotatable component 1 according to one embodiment of the invention. There is a certain overlap, with each transmitter 21 reaching two receivers 12 simultaneously before each of the receivers 12 disappears into the shadow of the other receiver 12 or moves out of range of the transmitter 21. This overlap can be used to synchronize the receivers 12 with the signal.

[0049] Fig. Figure 7 shows a schematic functional diagram of an imaging system with two transmitters 11 on a rotatable part and four stationary receivers 22 according to an embodiment of the invention. For each transmitter 11, a receiver 22 is located in the range of the respective fanned-out light wave. The transmitter 11 and receiver 22, as well as the width of the fanned-out light waves, are designed such that a minimal overlap always occurs during the transition from one receiver 22 to the next, allowing for seamless signal transmission.

[0050] Fig.8 shows a flowchart of a method for signal transmission in an imaging system with a rotatable component 1 according to an embodiment of the invention. The signal is sent from a rotating component 1 to a stationary component 2 or vice versa. In a first step 101, a light wave is generated onto which the signal is modulated. In a further step 102, the light wave is fanned out to generate a wider, fan-shaped light wave. In a further step 103, the light wave is sent to a receiver 12, 22. Finally, in a further step 104, the light wave with the modulated signal is detected by the receiver 12, 22.

Claims

[1] Transmitter (11, 21) for an imaging system, in particular a computer tomography system, for transmitting signals, in particular comprising data, wherein the transmitter (11, 21) comprises a light wave generator (3) and is configured to modulate the signals onto generated light waves (4) and to transmit them with the light waves (4, 6), wherein the transmitter (11, 21) comprises a fan-out optic which is designed to fan out the generated light waves (4, 6) in a plane. [2] Transmitter (11, 21) according to claim 1, wherein the fan-out optics comprises a line generator lens, in particular a Powell lens (5). [3] Transmitter (11, 21) according to one of the preceding claims, wherein the transmitter (11, 21) is designed to generate, in particular simultaneously, different light waves (4, 6) with different wavelengths. [4] Receiver (12, 22) for an imaging system for receiving signals modulated onto fanned-out light waves (6), wherein the receiver (12, 22) comprises a light guide optics and a light detector (9), wherein the light guide optics are designed such that they guide light arriving from an angular range in a light entry plane to the light detector (9) for each angle of the angular range. [5] Receiver (12, 22) according to claim 4, wherein the light-guiding optics comprises a conical mirror (7). [6] Receiver (12, 22) according to one of claims 4 to 5, wherein the angular range extends over at least 15°, preferably at least 45°, particularly preferably at least 90°, most particularly preferably at least 150°. [7] Receiver (12, 22) according to one of claims 4 to 6, wherein the receiver (12, 22) comprises a housing with a light input (10), wherein the light input (10) is designed to allow light entry according to the angular range, wherein the light guide optics and the light detector (9) are arranged in the housing. [8] Receiver (12, 22) according to claim 7, wherein the housing comprises a light-absorbing inner wall (8) at least in an area around the light detector (9). [9] Receiver (12, 22) according to claim 7 or 8, wherein the light-absorbing inner wall (8) also extends to an area behind the light guide optics opposite the light input (10). [10] Receiver (12, 22) according to one of claims 7 to 9, wherein the light inlet (10) of the housing is designed as a transparent cylinder section in the angular range, wherein in particular an axis of the cylinder runs substantially parallel to the axis of the conical mirror. [11] Receiver (12, 22) according to one of claims 4 to 10, wherein the receiver (12, 22) comprises a parabolic mirror (90) designed to deflect light rays onto the light detector (9), wherein the light detector (9) is arranged between the light guide optics and the parabolic mirror (90). [12] Imaging system with a rotatable component (1), in particular a computer tomography system with a rotatable gantry, and with a stationary component (2), wherein the imaging system comprises at least one transmitter (11, 21) according to one of claims 1 to 3 and at least one receiver (12, 22) for receiving signals modulated onto fanned-out light waves (6), in particular at least one receiver (12, 22) according to one of claims 4 to 11, wherein the at least one transmitter (11) is arranged on the rotatable component (1) and the at least one receiver (22) is arranged on the stationary component (2), so that the at least one transmitter (11) is at least temporarily aligned during a rotation of the rotatable component (1) such that light waves (6) can be transmitted from the at least one transmitter in the direction of the at least one receiver (22) and received by the at least one receiver (22); and / or wherein the at least one receiver (12) is arranged on the rotatable component (1) and the at least one transmitter (21) is arranged on the stationary component (2), such that the at least one transmitter (21) is at least temporarily aligned during a rotation of the rotatable component (1) such that light waves (6) can be transmitted from the at least one transmitter (21) in the direction of the at least one receiver (12) and received by the at least one receiver (12). [13] Imaging system according to claim 12, wherein the imaging system comprises a plurality of transmitters (11) on the rotatable component (1) and / or a plurality of receivers (22) on the stationary component (2), which are arranged such that a temporally seamless signal transmission of a signal is possible upon rotation of the rotatable component (1); and / or wherein the imaging system comprises a plurality of receivers (12) on the rotatable component (1) and / or a plurality of transmitters (21) on the stationary component (2), which are arranged such that a temporally seamless signal transmission of a signal is possible upon rotation of the rotatable component (1). [14] Imaging system according to one of claims 12 or 13, wherein the imaging system is designed to transmit a plurality of light waves (4, 6) each having different frequencies and each having at least one signal simultaneously from the at least one transmitter (11, 21) to the at least one receiver (12, 22). [15] Use of fanned-out light waves (6) for signal transmission in an imaging system with a rotatable component (1), in particular a computer tomography system with a rotatable gantry.

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