RU2237916C2 - Device for transforming flow of optical radiation - Google Patents

Abstract

FIELD: optical engineering.

SUBSTANCE: device has inlet 6 and outlet 8 ends connected by plurality of vacuumed or filed by other gas-like environment channels for transporting optical radiation. Extensions of outlet 7 and inlet 9 ends of channels beyond limits of input and output ends are directed in such a way, that in total they have shape of input and required output flows of optical radiation recognized by the device. One or two ends of device, excluding input and output apertures of channels, have non-transparent cover, or channels walls and environment between channels are non-transparent. If extensions of longitudinal axes of channels on the side of input and output ends cross in points placed on extension of longitudinal axis of device, it s capable of focusing divergent flow of optical radiation of quasi-dot source. If extensions of longitudinal axes of channels on the side of one of ends cross in a point placed on extension of device parallel axis, and extensions of longitudinal axes of channels on the side of another end are parallel to longitudinal axis of device, it transforms diverging flow of optical radiation of quasi-dot source into quasi-parallel.

EFFECT: separate transfer to output of radiation energy and respective optical information from different element of input flow formed by light source or lighted object.

2 cl, 13 dwg

Description

Technical field

The present invention relates to optics and is intended to convert the flow of optical radiation.

State of the art

Known devices for converting the flow of optical radiation, in particular for focusing divergent radiation from a source, converting such radiation to quasi-parallel, focusing quasiparallel radiation or scattering it (converting to divergent), etc. These devices are usually made in the form of optical lenses or convex or concave mirrors (Physical Encyclopedic Dictionary. - M.: Soviet Encyclopedia, 1984 [1], p. 347, 200).

Such devices, when used in optical systems to obtain an optical image or to convert a light stream coming from a light source, are characterized by various aberrations ([1], p.7), due, in particular, to the fact that light is transmitted from each point of the object to the image element corresponding to this point, the lens or the mirror as a whole is involved.

Closest to the proposed device are known devices made in the form of lenses. Optical lenses are close to the proposed device by the fact that they are usually used to convert the flow of paraxial rays incident on the lens at small angles to its optical axis. In this case, the input stream undergoes a transformation as a result of passing through the lens, falling on it on one side and exiting on the other.

Disclosure of invention

The technical result provided by the proposed device is the differential transfer to the output of the device of the radiation energy and the corresponding optical information from different elements of the input stream generated by the light source or illuminated object. Thanks to the independent transfer of energy (information) from different elements of the stream (points of an illuminated or luminous object), prerequisites are created for eliminating the causes of aberrations inherent in traditional lens systems, and the quality indicators of the device potentially depend only on the technological capabilities of its manufacture. Another type of technical result of the proposed device is that it is “automatically”, i.e. without any special measures, spatial sampling of the output stream is ensured. This makes it easy to pair the device with digital matrix converters.

Two versions of the device for converting the flow of optical radiation are offered.

According to the first embodiment, the device for converting the optical radiation flux is characterized in that it has an input and output ends connected by a plurality of channels. The channels are configured to transport optical radiation through them with reflection from their walls or without reflection. The extension of the channels beyond the input and output ends in the aggregate take the form of the input and required output optical radiation fluxes, respectively, perceived by the device. Moreover, in one of the proposed embodiments of the device, the input end or both ends of the device, with the exception of the inlet and outlet openings of the channels, have a coating made of a material opaque to the optical radiation of the used range.

According to the second embodiment, the device for converting the optical radiation flux has an input and output ends connected by a plurality of channels, which are configured to transport optical radiation through them with reflection from their walls or without reflection. The extension of the channels beyond the input and output ends in the aggregate take the form of the input and required output optical radiation fluxes, respectively, perceived by the device. The walls of the channels and the gaps between them are made of a material opaque to the optical radiation of the used range.

Thus, both options are the same in that they have many channels for transporting radiation from the input to the output of the device, the shape of the input stream (beam) for which the device is intended to work, and the shape of the output stream (beam) into which the input stream (beam) of optical radiation is converted, determined by the orientation of the ends of the channels from the input side and from the output side of the device (from the side of its input and output ends). Parts of the channels located between their end parts serve to mate the end parts.

The options differ in how the radiation from the input to the output of the device through the medium filling the gaps between the channels is excluded. In the first embodiment, a coating of one or both ends of the device is used, which is opaque to the radiation of the used range (the channel inlet and outlet openings are left open). In the second embodiment, the channel walls and the gaps between them are made of a material opaque to the optical radiation of the used range.

The following special cases of the device are possible in both versions.

The channels can be evacuated or filled with air or other gaseous media. In this case, the radiation loss is small when it passes through the channels.

The channels can be filled with a medium transparent to the radiation used, which is denser than their walls. In this case, it is possible to fulfill the condition of total internal reflection during the propagation of radiation through the channels.

The channels can be made with longitudinal axes curved along the generatrices of coaxial barrel-shaped surfaces. Moreover, if the extensions of the longitudinal axis of the channels from the input and output ends of the device intersect at points located on the extension of the longitudinal axis of the device, the latter is able to focus the diverging radiation of a point source. If the extensions of the longitudinal axis of the channels from the side of one of the ends of the device intersect at a point located on the extension of the longitudinal axis of the device, and the extensions of the longitudinal axis of the channels from the side of the other end of the device are parallel to the longitudinal axis of the device, the device converts the divergent radiation of the source into quasi-parallel or vice versa focusing quasi-parallel radiation.

With the above-mentioned execution of the channels, they can have a constant cross-sectional length or cross-section, the size of which changes according to the same law as the size of the device as a whole in the transverse direction.

The part of the device adjacent to its longitudinal axis can be made opaque to the radiation used. Due to this, in the case of using a device for focusing radiation, the size of the focal region in the longitudinal direction is reduced.

The device can be made in such a way that the extensions of the longitudinal axis of the channels from one of the ends intersect at a point located on the extension of the longitudinal axis of the device, or parallel to it, and the extensions of the longitudinal axis of the channels from the other end of the device diverge in different directions from the longitudinal axis devices. In this case, the device generates scattered radiation, respectively, from radiation that already has some divergence, or from quasi-parallel radiation.

The device can also be used to rotate radiation, for which it can have a longitudinal axis with one or more bends and channels equidistant to it.

Brief Description of the Drawings

The proposed device is illustrated by drawings, which show:

- figure 1 - the passage of radiation through a separate channel for various directions of entry of rays into the channel;

- figure 2 - the main parts of the device;

- figure 3 is a set of parallel input ends of the channels and the corresponding quasi-parallel input radiation stream;

- figure 4 is a set of converging ends of the channels, the continuations of which intersect at the point of location of the point source, and the diverging input radiation flux corresponding to this set;

- figure 5 is a device for focusing the optical radiation of a point source with a constant cross-sectional channel length;

- Fig.6 is a device for converting diverging optical radiation of a point source into quasi-parallel or for focusing quasi-parallel optical radiation with a constant cross-section of the channels;

- in FIGS. 7 and 8, respectively, the same as in FIGS. 5 and 6, with channels whose transverse dimensions vary in length according to the same law as the size of the device as a whole in the transverse direction;

- figure 9 is an example of a device with flat ends;

- figure 10 is an example of a device with a Central part, opaque to the radiation used;

- figure 11 - the use of the proposed device for imaging an object;

- Fig.12 is an example embodiment of a device for converting a quasi-parallel stream of optical radiation into scattered radiation;

- Fig.13 is an example embodiment of a device with equidistant curved channels.

Embodiments of the invention

The principle of operation of the proposed device is based on the transmission of radiation from its input to output through many separate channels. If the radiation source 1 (FIG. 1) is within the extension 2 of the input end 3 of channel 4, then this radiation (see, for example, beam A in FIG. 1) enters the channel 4 at a small angle to its walls and passes to the exit channel with a minimum number of reflections from its walls. Radiation emanating from points located differently (for example, beam B in FIG. 1, emanating from point 5) enters the channel 4 at a large angle and experiences a greater number of reflections, as a result of which it is weakened to a greater extent. The difference in the conditions of passage of rays A and B is the greater, the smaller the size d of the channel in the transverse direction.

The input of the device is its input end 6 (figure 2), formed by a combination of one ends of the 7 channels, and the output is the output end 8, formed by a combination of other ends 9 of the channels.

The ends of the channels in the manufacture of the device are oriented in such a way as to ensure consistency with the shape of the beam of radiation that you want to convert. For this, the set of channel extensions towards the radiation source must have the same shape as the converted beam. So, to convert a parallel or quasi-parallel beam 10 (Fig. 3), the continuation of 11 input ends 12 of the device channels must be parallel to each other, and the combination of their cross sections to completely capture the source radiation must be the same as the cross section of the converted beam or fully include the cross section of the converted beam. To convert the beam 13 (figure 4) of the diverging radiation of a point or quasi-point source 14, the continuation of 15 input ends 16 of the device channels must intersect at the source location. Only that part of the source radiation that is emitted by it within the solid angle formed by the set of continuations of the input ends of the channels will be captured and transformed. Similarly, the orientation of the extensions of the output ends of the channels is selected based on the desired shape of the output beam, and the dimensions of the cross section of this beam are determined by the total cross section of the output ends of the channels.

The shape of the parts of the channels located between their end parts is selected based on the condition of smooth conjugation of the end parts.

The central (adjacent to the longitudinal axis of the device) channels having a small curvature or rectilinear radiation can be transported without reflection from their walls.

The proposed device in both variants described above during the disclosure of the invention may include channels 4 for transporting optical radiation with a constant cross-sectional length (FIGS. 5, 6). In this case, the device is assembled from separate identical channels, for example, glass capillaries using various separation elements to give the channels and the device as a whole the desired shape, similar to how the x-ray lenses are assembled according to US patent No. 5192869 (publ. 09.03.93) [2]. The role of the end portion impervious to radiation of the used range in the device according to the first embodiment can be performed by a continuous dividing element with openings for the ends of the channels. The device according to the second embodiment can also be manufactured according to the technology described in [2], which provides instead of using separating elements to fill the space between the channels with a compound. According to the invention according to the second embodiment, the compound must be impermeable to the optical radiation used.

Channels 4 may have a cross-section, the size of which varies (Fig.7, 8) according to the same law as the size of the device as a whole in the transverse direction. In this case, for the manufacture of the device, the technology for drawing glass blanks described in the patent of the Russian Federation No. 2096353 (publ. 20.11.97 [3]) is applicable. This technology, in which the process can be largely automated, is more advanced than the assembly technology. However, the most promising is the technology used for the manufacture of so-called integral x-ray lenses (patent of the Russian Federation No. 2164361, publ. 03.20.2001 [4]; US patent No. 6271534, publ. 07.08.2001 [5]), which allows to obtain devices with large the number of channels of micron and submicron diameter. After the implementation of the stages of technological processes according to [4] or [5], a monolithic device is obtained having ends formed by the fused ends of the channels. To complete the manufacture of the device according to the first proposed embodiment, on the surface of one or both ends formed by the gaps between the channels, a material impermeable to the radiation used (for example, is sprayed). In particular, it may be a sprayed reflective radiation material. In this case, there is no need to take measures to prevent it from entering the channels and settling on their walls. For the manufacture of the device according to the second embodiment, tubular blanks of future channels are used, made of a material opaque to the radiation of the used range, for example, stained glass.

In all described cases of the device for its proper operation, it is important that radiation from the input to the output of the device through the medium filling the gaps between the channels is excluded. This is ensured by the above measures, due to which only radiation transported through the channels is involved in the formation of the output stream. From the input side, the channels provide the required selectivity, and their output ends give the radiation the desired direction. If such measures are not taken, the radiation can pass through the walls of the channels from one channel to another, propagate between the channels and penetrate the device output not through the channel outlet or through them, but in arbitrary directions. As experiments show, as a result of this, in particular, the effects of focusing or the formation of a quasi-parallel flow are not achieved.

5 to 9, vertical shading shows the spatial zones formed by the set of extensions of the ends of the channels 4 beyond the input and output ends. These zones have the shape of the input and the required output optical radiation fluxes respectively perceived by the device. For all devices, the reversibility property holds. So, for the focusing devices shown in FIGS. 5 and 7, any of the ends can be input, while the other will be output. The devices shown in FIGS. 6 and 8, when a divergent stream of radiation of a source, for example a point source, is fed from the left end side, a quasi-parallel radiation stream forms at the output, and when such radiation is supplied from the right end side, a focused radiation stream is generated. The devices shown in FIGS. 5 and 7 are barrel-shaped, and the devices shown in FIGS. 6 and 8 resemble a half-barrel. In both cases, the axial lines of the channels, except for the central ones (adjacent to the longitudinal axis of the device), are curved along the generatrices of barrel-shaped surfaces.

The ends of the device can be rounded, like both ends of the devices in FIGS. 2, 5, 7 and the left ends of the devices in FIGS. 6, 8, or flat, like the right ends of the devices in FIGS. 6, 8, or both ends of the device in FIG. 9. The execution of the ends flat is advisable when the radiation entering this end or leaving the radiation is quasi-parallel, as well as in cases where the channels are evacuated or filled with a gaseous medium other than air. In these cases, to ensure tightness, the ends are coated with a film transparent to the radiation used.

The channels can also be filled with a medium denser than their walls. As such channels, for example, optical fibers with a quartz core can be used. In this case, the energy loss of the radiation during its transportation through the channels can be reduced by using the phenomenon of total internal reflection.

When using the proposed device for focusing optical radiation, the focal region can be strongly blurred in the longitudinal direction due to the presence of rectilinear or slightly curved central (located near the longitudinal axis of the device) channels. The quality of focusing can be improved by performing part of the device adjacent to its longitudinal axis, opaque to the radiation used. This can be ensured as the implementation of this part (position 17, figure 10) continuous of an opaque material, i.e. not containing channels, and by blocking the inputs or outputs of the central channels after manufacturing a device containing such channels. The reduction in the size of the focal region 18 in the longitudinal direction is achieved due to the fact that it is formed by the radiation of only peripheral channels emerging from them at an angle to the longitudinal axis 19 of the device.

By analogy with traditional optical lenses and taking into account the functions performed, the proposed device in the considered cases of its implementation can be called a lens. When using such a lens as a means for forming an image of a flat object, each channel serves to transmit information about only one element of the object located at the continuation of the input end of this channel. As noted above, the influence of elements that are away from this continuation, the less, the smaller the diameter of an individual channel. When using the device 20 (Fig. 11) of the type shown in Figs. 5, 7, 9, the image 21 of the object 22 can be obtained in any plane perpendicular to the longitudinal axis 23 of the device, to the right of its output end (to the right and to the left output focus 24, which is understood as the point of intersection of the extensions of the longitudinal axis of the channels from the side of their outputs). The object 22, the image of which is being formed, can be placed both to the right and to the left of the input focus 25, which is understood as the point of intersection of the extensions of the longitudinal axes of the channels from the side of their inputs. In the case shown in FIG. 11, the object 22 is located to the left of the input focus 25, and the resulting image is to the right of the output focus 24, i.e. the plane of the object and the image are removed from the corresponding ends by distances L ₁ and L ₂ , which are more than the focal lengths f ₁ and f ₂ (the latter mean the distance from the input (output) of the central channel to the corresponding focus).

The image in this case is “not flipped”. A point element of an object corresponds to an image element having a minimum size of the order of d (1 + 2L ₂ / L ₁ ), where d is the transverse dimension of the channel (with a circular cross section of the channel, its diameter). Since when obtaining images of macro objects, usually L ₂ << L ₁ (this ratio takes place in traditional photography), the minimum image element has a size on the order of the channel diameter d.

On Fig shows a special case of the device 26 for converting a quasi-parallel stream of optical radiation 27 into scattered radiation 28. In this case, the output ends of the channels 4 diverge in different directions from the longitudinal axis of the device.

The device 29 shown in FIG. 13 is designed so that the longitudinal axis of its channels is equidistant and bent to rotate the beam 30 of the quasi-parallel radiation beam converted to the beam 31.

In all described cases of the device for its proper operation, it is important that radiation from the input to the output of the device through the medium filling the gaps between the channels is excluded. This is achieved, as noted above, by applying a coating of one or both ends of the device (except for the inlet and outlet openings of the channels), which is opaque to the optical radiation used, or by making the walls of the channels and the gaps between them from an opaque material. Due to this, only radiation transported through the channels is involved in the formation of the output stream. From the input side, the channels provide the required selectivity, and their output ends give the radiation the desired direction. As experiments show, if such measures are not taken, radiation can pass through the channel walls from one channel to another and propagate between the channels, as a result of which, in particular, focusing effects or the formation of a quasi-parallel flow are not achieved.

Industrial applicability

The proposed device can be implemented in practice in any of the described possible options, depending on the desired nature of the conversion of the optical radiation flux, technological capabilities and other grounds for certain preferences.

Sources of information

1. Physical encyclopedic dictionary. - M.: Soviet Encyclopedia, 1984.

2. US patent No. 5192869 (publ. 09.03.93).

3. Patent of the Russian Federation No. 2096353 (publ. 20.11.97).

4. Patent of the Russian Federation No. 2164361 (publ. March 20, 2001).

5. US patent No. 6271534 (publ. 07.08.2001).

Claims (16)

1. Device for converting a stream of optical radiation, characterized in that it has an input (6) and output (8) ends connected by a plurality of channels (4) evacuated or filled with a gaseous medium, configured to transport optical radiation through them with reflection from them walls or without reflection, the continuation (11, 15) of the channels beyond the input and output ends in the aggregate have the shape of the input and required output optical radiation fluxes respectively perceived by the device, while Khodnev end or both end of said device, except for inlets and outlets of said channels have a coating made of a material opaque to optical radiation band used. 2. The device according to claim 1, characterized in that part (17) of the device adjacent to its longitudinal axis is made opaque to the radiation used. 3. The device according to claim 1 or 2, characterized in that the channels are made with longitudinal axes curved along the generatrices of coaxial barrel-shaped surfaces. 4. The device according to claim 3, characterized in that the continuation of the longitudinal axes of the channels (16) from the input and output ends of the device intersect at points (14) located on the continuation of the longitudinal axis of the device. 5. The device according to claim 3, characterized in that the extensions of the longitudinal axis of the channels from one of the ends of the device intersect at a point located on the extension of the longitudinal axis of the device, and the extensions (11) of the longitudinal axis of the channels (12) from the other end of the device are parallel longitudinal axis of the device. 6. The device according to claim 4 or 5, characterized in that the channels have a constant length cross-section or cross-section, the size of which varies according to the same law as the size of the device as a whole in the transverse direction. 7. The device (26) according to claim 1 or 2, characterized in that the continuation of the longitudinal axis of the channels from one of the ends of the device intersect at a point located on the continuation of the longitudinal axis of the device or parallel to it, and the continuation of the longitudinal axis of the channels from the other end devices diverge in different directions from the longitudinal axis of the device. 8. The device (29) according to claim 1 or 2, characterized in that its longitudinal axis has one or more bends and the channels are equidistant to it. 9. Device for converting the flow of optical radiation, characterized in that it has an input (6) and output (8) ends connected by a plurality of channels (4) evacuated or filled with a gaseous medium, configured to transport optical radiation through them with reflection from them walls or without reflection, the continuation (11, 15) of the channels beyond the input and output ends in the aggregate have the shape of the input and required output optical radiation fluxes respectively perceived by the device, while Tenkai radiation transporting channels, and the spaces between them are made of material opaque to optical radiation band used. 10. The device according to claim 9, characterized in that the part (17) of the device adjacent to its longitudinal axis is made opaque to the radiation used. 11. The device according to claim 9 or 10, characterized in that the channels are made with longitudinal axes curved along the generatrices of coaxial barrel-shaped surfaces. 12. The device according to claim 11, characterized in that the extensions of the longitudinal axes of the channels (16) from the input and output ends of the device intersect at points (14) located on the extension of the longitudinal axis of the device. 13. The device according to claim 11, characterized in that the extensions of the longitudinal axis of the channels from one of the ends of the device intersect at a point located on the extension of the longitudinal axis of the device, and the extensions of the longitudinal axis of the channels (12) from the other end of the device are parallel to the longitudinal axis of the device . 14. The device according to item 12 or 13, characterized in that the channels have a constant cross-sectional length or cross-section, the size of which varies according to the same law as the size of the device as a whole in the transverse direction. 15. The device (26) according to claim 9 or 10, characterized in that the extensions of the longitudinal axis of the channels from one of the ends of the device intersect at a point located on the extension of the longitudinal axis of the device, or parallel to it, and the extension of the longitudinal axis of the channels from the other the ends of the device diverge in different directions from the longitudinal axis of the device. 16. The device (29) according to claim 9 or 10, characterized in that its longitudinal axis has one or more bends and the channels are equidistant to it.

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