Lightweight and low f-number lens and method of manufacture
阅读说明:本技术 轻量且低f数的透镜及制造方法 (Lightweight and low f-number lens and method of manufacture ) 是由 尤瓦尔·伊斯比 沙哈尔·哈尼亚 阿兰·盖勒 于 2019-01-28 设计创作,主要内容包括:通常,公开一种用于收集来自小的和/或远处物体的光的光学单元。光学单元可包括直径为至少150mm的前透镜和与该前透镜相关联的至少一个附加透镜,其中前透镜由硫属化合物玻璃制成。在一些实施例中,光学单元的重量在2至6kg之间。(Generally, an optical unit for collecting light from small and/or distant objects is disclosed. The optical unit may comprise a front lens having a diameter of at least 150mm and at least one additional lens associated with the front lens, wherein the front lens is made of chalcogenide glass. In some embodiments, the weight of the optical unit is between 2 and 6 kg.)
1. An optical unit for collecting light from small or distant objects, the optical unit comprising:
a front lens having a diameter of at least 150 mm; and
at least one additional lens associated with the front lens;
wherein the front lens is made of chalcogenide glass.
2. The optical unit of claim 1 weighing between 2kg and 6 kg.
3. An optical unit according to claim 1 or 2 having an f-number of not more than 1.4.
4. The optical unit according to any one of claims 1 to 3 having a focal length of not more than 150 mm.
5. An optical unit according to any one of claims 1 to 4, wherein the rate of change of the refractive index of the front lens does not exceed 551/° C.
6. A system for detecting and identifying small or distant objects by moving trains, the system comprising:
an optical unit comprising: a front lens having a diameter of at least 150mm and made of chalcogenide glass; and at least one additional lens associated with the front lens;
a detector associated with the optical unit, wherein the optical unit is arranged to collect light from the small or distant object onto the detector, and wherein the detector is arranged to produce at least one image based on the collected light; and
a processing unit coupled to the detector and configured to identify a trajectory in the at least one image and to identify the small or distant object on the trajectory or in a defined vicinity of the trajectory in the at least one image.
7. The system of claim 6, wherein the optical unit weighs between 2kg and 6 kg.
8. The system of claim 6 or 7, wherein the f-number of the optical unit is not greater than 1.4.
9. The system of any one of claims 6 to 8, wherein the focal length of the optical unit is not less than 150 mm.
10. The system of any one of claims 6 to 9, wherein the rate of change of the refractive index of the front lens of the optical unit does not exceed 551/° c.
11. The system of any one of claims 6 to 10, wherein the detector is an infrared camera.
12. The system of any one of claims 6 to 11 being mountable on a locomotive of the train such that the optical unit and the detector face in a direction of travel of the train.
Technical Field
The present invention relates to the field of low f-number lenses, and more particularly, to low f-number lenses for collecting light from small and/or distant objects.
Background
Current optical units for collecting light from small and distant objects are typically heavy and large in size. This is especially the case when the optical unit is designed to withstand a large operating temperature range.
For example, FIG. 1 shows a typical current
Typically, the front lens 92 (or aperture) of the
Since germanium is a relatively heavy crystal (e.g., 72.63u atomic mass), the current
Furthermore, lenses made of germanium (e.g., such as the
Disclosure of Invention
One aspect of the present invention provides an optical unit for collecting light from a small or distant object, which optical unit may comprise a front lens having a diameter of at least 150mm and at least one additional lens associated with the front lens, wherein the front lens is made of chalcogenide glass.
In some embodiments, the weight of the optical unit is between 2 and 6 kg.
In some embodiments, the f-number of the optical unit is no greater than 1.4.
In some embodiments, the focal length of the optical unit is no greater than 150 mm.
In some embodiments, the rate of change of the refractive index of the front lens does not exceed 551/C.
Another aspect of the present invention provides a system for detecting and identifying small or distant objects by moving a train, which may include: an optical unit comprising a front lens having a diameter of at least 150mm and made of chalcogenide glass, and at least one additional lens associated with the front lens; a detector associated with the optical unit, wherein the optical unit is arranged to collect light from small or distant objects onto the detector, and wherein the detector is arranged to produce at least one image based on the collected light; and a processing unit coupled to the detector and configured to identify the trajectory in the at least one image and to identify small or distant objects on the trajectory or in a defined vicinity of the trajectory in the at least one image.
In some embodiments, the weight of the optical unit is between 2 and 6 kg.
In some embodiments, the f-number of the optical unit is no greater than 1.4.
In some embodiments, the focal length of the optical unit is not less than 150 mm.
In some embodiments, the rate of change of the refractive index of the front lens of the optical unit does not exceed 551/C.
In some embodiments, the detector is an infrared camera.
In some embodiments, the system may be mounted on a locomotive of a train such that the optical unit and detector face in the direction of travel of the train.
These, additional, and/or other aspects and/or advantages of the present invention are set forth in the detailed description that follows; may be inferred from the detailed description; and/or may be learned by practice of the invention.
Drawings
For a better understanding of embodiments of the present invention and to show how the same may be carried into effect, reference will now be made, by way of example only, to the accompanying drawings in which like reference numerals refer to corresponding elements or parts throughout.
In the drawings:
FIG. 1 shows a typical current optical unit for collecting light from small and distant objects;
fig. 2 is a schematic diagram of a system for detecting and identifying obstacles by moving trains according to some embodiments of the present invention; and
FIG. 3 is a schematic diagram of an optical unit for collecting light from small and/or distant objects according to some embodiments of the invention.
It will be appreciated that for simplicity and clarity of illustration, elements shown in the figures have not necessarily been drawn to scale. For example, the dimensions of some of the elements may be exaggerated relative to other elements for clarity. Further, where considered appropriate, reference numerals may be repeated among the figures to indicate corresponding or analogous elements.
Detailed Description
In the following description, various aspects of the present invention are described. For purposes of explanation, specific configurations and details are set forth in order to provide a thorough understanding of the present invention. It will be apparent, however, to one skilled in the art that the present invention may be practiced without the specific details presented herein. In addition, well-known features may be omitted or simplified in order not to obscure the present invention. With specific reference to the drawings, it is stressed that the particulars shown are by way of example and for purposes of illustrative discussion of the present invention only, and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the invention. In this regard, no attempt is made to show structural details of the invention in more detail than is necessary for a fundamental understanding of the invention, the description taken with the drawings making apparent to those skilled in the art how the several forms of the invention may be embodied in practice.
Before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of the components set forth in the following description or illustrated in the drawings. The invention is applicable to other embodiments and combinations of the disclosed embodiments, which may be practiced or carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein is for the purpose of description and should not be regarded as limiting.
Referring now to fig. 2, fig. 2 is a schematic diagram of a system 100 for detecting and identifying obstacles by a moving
According to some embodiments, the system 100 includes an optical unit 110 associated with the detector 120 and a processing unit 130 coupled to the detector 120. The system 100 may be disposed on, for example, a
The optical unit 110 may collect light 60 from the environment onto the detector 120. The detector 120 (e.g., an infrared camera) may generate an image of the environment based on the collected light. The processing unit 130 may be configured to analyze the images generated by the detector 120 and identify the rail 80 in the images (e.g., based on the inherent temperature difference between the rail 80 and the environment) and/or identify potential objects/obstacles 70 on the rail 80 or in a defined vicinity of the rail 80 (e.g., based on the temperature difference between the object/obstacle 70, the rail 80, and the environment).
The required performance of the system 100 should ensure that small and/or distant objects/obstacles 70 on the track 80 and in the vicinity of the track 80 are well detected and identified in advance to enable safe braking before the
For example, for a
The desired performance of the system 100 should further ensure stable optical performance over a specified ambient temperature range. For example, the system 100 must perform stably and robustly at ambient temperatures between-35 deg. -55 deg.C.
To meet the above requirements, the optical unit 110 of the system 100 must be capable of efficiently collecting light from small and/or remote objects 70 within a specified temperature range (e.g., as described above).
Current optical units (e.g.,
However, such heavy optical units (e.g., the current optical unit 90) may be subject to large acceleration forces, motions, and vibrations during movement of the
Furthermore, a lens made of germanium (e.g.,
This, therefore, has led to efforts to develop specially designed optical units 110 that can meet the above-described requirements of system 100 (e.g., as described below with respect to fig. 3).
Referring now to fig. 3, fig. 3 is a schematic diagram of an
According to some embodiments, the
According to some embodiments, the
The
The inventors have found that in order to effectively collect light from small and/or distant objects within an extended ambient scene (e.g. objects/obstacles 70 that are about 50cm wide, such as at a distance 72 of about 2km from the optical unit, as described above with respect to fig. 2), the
For example, an extended environmental scene (hereinafter interchangeably referred to as "extended source", E) in the plane of the
wherein L is the emittance (e.g., in W/cm)2Steroadian), I is the radiation intensity (e.g., in W/steroadian), ΩoptIs the solid angle, and λ is the wavelength (e.g., in cm).
For example, for an
Thus, the smaller the F-number F/# of the
In some embodiments, the f-number of the
In some embodiments, the focal length f of the
Such a small F-number (e.g., F/#) and such a large focal length (e.g., F) may require that the
for example, if the F-number of the
In some embodiments, the diameter of the
In some embodiments, the
The optical properties of the
In some embodiments, the
The inventors have discovered that making the
For example, the rate of change of the refractive index of the
Furthermore, the weight of the
Furthermore, the
Advantageously, the use of chalcogenide glass for large apertures/front lenses, e.g., greater than 200mm (e.g.,
For example, the disclosed optical unit (e.g.,
Furthermore, the disclosed optical unit may significantly reduce the complexity and/or cost of the stabilization and aiming devices for its optical unit (e.g., as compared to those required for the current
Furthermore, the disclosed optical unit may provide passive compensation of the thermal instability of the lens (e.g., due to the
In the foregoing description, an embodiment is an example or implementation of the present invention. The various appearances of "one embodiment," "an embodiment," "some embodiments," or "some embodiments" are not necessarily all referring to the same embodiments. While various features of the invention may be described in the context of a single embodiment, these features may also be provided separately or in any suitable combination. Conversely, although the invention may be described herein in the context of separate embodiments for clarity, the invention may also be implemented in a single embodiment. Certain embodiments of the invention may include features from different embodiments disclosed above, and certain embodiments may include elements from other embodiments disclosed above. In the context of particular embodiments, the disclosure of elements of the invention should not be taken to limit their use only in the particular embodiments. Further, it is to be understood that the invention may be embodied or practiced in various ways and that the invention may be practiced in certain embodiments other than those outlined in the description above.
Unless defined otherwise, the meanings of technical terms used herein are generally understood by those of ordinary skill in the art to which the present invention belongs. While the invention has been described with respect to a limited number of embodiments, these should not be construed as limitations on the scope of the invention, but rather as exemplifications of some of the preferred embodiments. Other possible variations, modifications, and applications are also within the scope of the invention. Accordingly, the scope of the present invention should not be limited to that described so far, but should be defined by the appended claims and their legal equivalents.