WO2019137819A1

WO2019137819A1 - Projection device for data spectacles and data spectacles of this kind

Info

Publication number: WO2019137819A1
Application number: PCT/EP2018/097098
Authority: WO
Inventors: Simone Hoeckh; Tobias Graf
Original assignee: Robert Bosch Gmbh
Priority date: 2018-01-10
Filing date: 2018-12-28
Publication date: 2019-07-18
Also published as: DE102018201525A1

Abstract

The invention relates to a projection device (100) for data spectacles (400) having at least one temple (118), wherein the projection device (100) has the following features: at least one light source (104) for emitting at least one light beam (106); at least one first deflection element (102) which is arranged or can be arranged on a spectacle lens (402) of the data spectacles (400) for projecting an image onto a retina (110) of a user of the data spectacles (400) by deflecting and/or focussing the at least one light beam (106) onto an eye lens (108) of a user; and at least one reflection element (112) for reflecting the light beam (106) onto the first deflection element (102). The projection device (100) further comprises a light guide (124) which is arranged between the light source (104) and the reflection element (112). The invention further relates to data spectacles.

Description

description

title

Projection device for data glasses and such data glasses

The present invention relates to a projection device for data glasses, and such data glasses.

State of the art

The development of helmet-mounted or head-mounted (HMD) or headworn displays (HWD) has been an active area of research since the 1960s. One feature is Virtual Reality (VR) systems. Above all, however, it is the development of augmented reality (AR) or mixed-reality devices that promises interesting possibilities for situational and individualized information provision in work and everyday life.

Due to high costs and bulky optics, HMDs are still used primarily in the military sector. However, also civilian professional groups and consumers in everyday life and leisure time of a handy and

benefit from low cost HMD device. But so far no one could

Consumer product in mass production successfully placed on the market. A big challenge here are e.g. mutually influencing requirements for the optical and mechanical specifications. There are currently two different types of HMDs on the market. On the one hand, these are lightweight, handy HMDs, whose imaging and sensory system is kept as small as possible, which is why they have only a limited

Have feature. On the other hand, there are HMDs with relatively bulky optics, possibly in combination with multiple sensors and cameras, which provide more sophisticated imaging and interactions between the

Environment perception and the superimposed image information allow However, they are much larger, heavier and less ergonomic to handle.

One approach to realize sophisticated imaging with a space-saving design is a laser-based retinal scanner (retina scanner device = RSD). In contrast to most other concepts, this does not use an imaging optic, which is an image of a

Display area via an imaging system in the field of view of the user einblendet. Instead, at least one, at

Polychromatic systems also generated by means of multiple laser sources, a beam that can be directed through a MEMS (micro-electro-mechanical system) level and scanned by means of mirror deflection over the retina. By latency in the human visual system can thus be generated by targeted control of mirror and laser source, the impression of a flat image or superimposed image content. The advantage of this system concept is the low number of optical components, which also require only little space.

Disclosure of the invention

The projection device for data glasses has at least one light source for emitting at least one light beam. The data glasses have at least one, in particular two, temples.

Data glasses can be understood to mean an HMD or a HWD. The term data glasses can also be understood to mean AR, VR or MR glasses, video glasses, a helmet display or an AR, VR or MR helmet.

A light source may be understood to mean a light-emitting element such as a light-emitting diode, in particular an organic light-emitting diode, a laser diode or an arrangement of a plurality of such light-emitting elements. In particular, the light source can be designed to emit light of different wavelengths. The light beam can for

Generating a plurality of pixels serve on the retina, wherein the Light beam the retina, for example, in rows and columns or in the form of Lissajous patterns sweeps and can be pulsed accordingly. Under a spectacle lens can be understood a made of a transparent material such as glass or plastic disc element. Depending on

Embodiment, the spectacle lens may be formed approximately as a correction glass or a tint for filtering light of certain wavelengths such as

for example, have UV light.

A light beam can be understood in the paraxial approximation to be a Gaussian beam.

The projection device furthermore has at least one first deflection element which is arranged or can be arranged on a spectacle lens of the data glasses

Projecting an image on a retina of a user of the data glasses by deflecting and / or focusing the at least one light beam on an eye lens of the user. The first deflecting element may e.g. on

holographic element or a free-form mirror.

By a holographic element, for example, a holographic optical device, HOE for short, can be understood, which is e.g. can perform the function of a lens, a mirror or a prism. Depending on

Embodiment, the holographic element for certain colors and angles of incidence can be selective. In particular, the holographic element can fulfill optical functions that can be imprinted into the holographic element with simple point light sources. As a result, the holographic element can be produced very inexpensively.

The holographic element can be transparent. Thereby can

Image information to be overlaid with the environment.

By means of a holographic element arranged on a spectacle lens of a data goggle, a light beam can thus be applied to a retina of a wearer of the

Data goggles are directed that the wearer perceives a sharp virtual image. For example, the image may be scanned by scanning a laser beam a micromirror and the holographic element are written directly on the retina.

Such a projection device can be built in a small space

be realized comparatively inexpensive and makes it possible to bring a picture content in a sufficient distance to the carrier. This allows the contact-analogous superimposition of the image content with the environment. The combination of scanning laser beam and deflecting element on the spectacle lens makes it possible to generate light stimuli directly on the retina, without the need for intermediate imaging of a flat display element. In addition, with such a flying-spot approach, a great depth of focus can be achieved.

In general, the deflection behavior on the surface of the holographic element is different at each point. As already mentioned above, it is generally not the case that the angle of incidence equals the angle of reflection. The portion of the surface of the holographic element which serves to redirect the light beam to the eye of a user is referred to as a functional region. For a free-form mirror, the same applies in principle as for a holographic element in the sense that the deflection behavior on the surface is locally different. However, in contrast to the holographic element, the law of reflection applies locally, i. that angle of incidence is the same

Fail angle is.

Furthermore, the projection device has at least one reflection element for reflecting the light beam onto the first deflection element. Under a reflection element, for example, a mirror, in particular a

Micromirror or an array of micromirrors, or a hologram can be understood. By means of the reflection element, a beam path of the light beam can be adapted to given spatial conditions. For example, the reflection element can be realized as a micromirror. The micromirror can be designed to be movable, for example, have a mirror surface which can be tilted about at least one axis. Such a system offers the advantage of a particularly compact design, which results from the fact that in no case the entire image must be represented by an imaging element, since the image to the first Time is created on the retina. This arises from the fact that a single beam is rastered by the movable reflection element over the retina. The aperture of this reflection element and thus the

Reflection element itself can therefore be much smaller than an imaging element which generates an image of a flat display. It is also advantageous if the reflection element is designed to change an incident angle and, additionally or alternatively, a point of impact of the light beam on the first deflection element, in particular the holographic element. As a result, the first deflecting element can be swept over the surface, in particular approximately in rows and columns, with the light beam.

Furthermore, the reflection element may be a mirror with a deformable surface. This has the advantage that the reflection element can not only deflect the light beam, but also change beam parameters. This can reduce the number of adaptive optical elements.

Furthermore, the projection device has a light guide, which is arranged between the light source and the reflection element. The light guide is preferably arranged between a second deflection element and the light source or the light module. The use of a light pipe has a number of advantages, which are explained below.

According to a preferred embodiment, the light guide has a

Optical fiber, a fiber optic cable or a photonic crystal on.

The optical waveguide is preferably an optical waveguide, an optical waveguide cable or a photonic crystal.

As light guides for certain wavelength ranges transparent components such as fibers, tubes or rods are referred to transport the light over short or long distances. The light pipe is achieved by reflection at the interface of the light guide either by total reflection due to a lower refractive index, the medium surrounding the light guide or by mirroring the interface. Since an optical fiber often consists of glass fibers, this is also referred to as fiber optic cable or fiber optic cable. The partially or completely plastic-based fibers such as the polymeric optical fibers and Hard Clad Silica Optical Fiber are also optical fibers.

Planar optical waveguide structures which are used in components of the integrated optics, such. B. switches and switches for the optical

Telecommunications are also optical fibers. The light guides also include light-conducting components made of plastic, such. PMMA or polycarbonate, for displays or for backlighting (Edge Lit Display).

Fiber optic cables and optical cables are made of optical fibers and partially assembled with connectors cables and cables for the transmission of light.

The light guide is a single-mode or a single-mode optical fiber. In

Multimode light guides can spread several thousand modes. They have a highly structured beam profile. In monomode fibers, which usually have a very small core diameter, only the so-called fundamental mode can be propagated, the intensity of which is approximately normally distributed in the radial direction. The advantage of using a monomode optical waveguide is that only the mode for which the monomode optical waveguide is designed can be coupled in and only this mode is transported in the optical waveguide. This mode may preferably be a fundamental mode, i. be the TEMOO-mode. As a result, a light profile coupled into the light guide is cleaned, i. Fashions that are not the

Are basic mode, are removed from the light profile. This causes a better image quality of the data glasses or the projection device. Better mode also results in more efficient diffraction at the HOE, if used, thereby requiring less light output. This in turn allows the

Electronics are smaller and lighter and produce less waste heat. An improved mode also produces less interference effects on the deflection element, eg on the HOE. Improved beam quality also adds to the smallness of the spot size, allowing for a more efficient system, which in turn means that less light needs to be provided. Less power required may allow the reduction of the electrical system. In addition, more efficient diffraction means less stray light. According to a preferred embodiment, the light source is or has a laser diode. The advantage of this feature, in particular in conjunction with the feature that it is a single-mode light guide, is, in addition to the pure transport of light, that at the end of the light guide a light profile emerges with extremely well-controlled parameters, ie these parameters are very robust and remain despite manufacturing tolerances,

Temperature fluctuations, shocks and aging effects very constant. These well-controlled and very constant parameters make the image impression consistently good for the user, and the properties calculated or designed in the design of the data glasses can be implemented in the hardware.

A photonic crystal is an artificially produced dielectric medium in which the refractive index varies spatially periodically. The special property of the photonic crystals is that they have a photonic band structure analogous to the formation of the electronic band structure in semiconductors. Among other things, this band structure has areas in which electromagnetic waves within the crystal can not propagate. These forbidden areas are called photonic band gaps.

Preferably, an optical fiber is used in the projection device per wavelength used. As a result, each wavelength can be optimally processed and transported.

Preferably, the waveguide is made so that it has at least two

different wavelengths singlemodig can transmit. As a result, the waveguide can advantageously transport two different wavelengths in each case in one mode.

The optical waveguide is preferably polarization-preserving. This has, inter alia, the advantage that the polarization is maintained during transmission through the waveguide and thus the properties of the light striking the eye are in turn better known and kept constant. According to a preferred embodiment, the light guide is arranged along the at least one eyeglass temple. This has the advantage that the light guide can be arranged very space-saving. This also allows for significant design freedom in both the design of the module containing the light sources and the overlay optics, as well as in the geometrical arrangement relative to the other optical elements. The former can be attached eg behind the ear. In the waveguide, the light can be led forward in the direction of the hinge, where it is deflected to meet the micromirror. Weight and volume are clearly distributed

even. With regard to the beam quality, it is important to note that the deflection at the front, hinge - near end of the eyeglass temple can take place via two 45 ° reflections. In this case the beam profile, e.g. on

Gauss profile, received.

According to a preferred embodiment, the light guide is designed monolithic. Particularly preferably, the light guide is designed monolithically with another optical component. The monolithic design has the advantage of increased stability and increased manufacturability. Furthermore, with sufficient manufacturing tolerance, reproducibility will increase because monolithic elements need not be adjusted individually for each projection device. Since less misalignment can take place, the

Robustness of the system while wearing. In addition, the space taken up and preferably also the weight are reduced.

It is also possible to achieve a better or more flexible spatial distribution of weight and volume. For example, an attachment of the light sources behind the ear to the fact that the mass of the front part of the glasses, which already contains the lenses, is not unnecessarily increased further. It also results in a favorable position of the center of gravity with appropriate edition of the glasses on the ears and nose. This secure fit results in a lower probability of damage and increased wearing comfort of the data glasses. Furthermore, it is associated with increased safety for use in e-bike, motorcycle or sports such as downhill mountain bikers or freeriders. Due to the monolithic design, the manufacturing costs can also be reduced. The light guide is preferably monolithic with a second deflection element. This has the advantage that only a monolithic component is thus arranged between the deflection element and the light source or the assembly which has the light source. This has the advantage of increased stability and adjustability.

According to a preferred embodiment, the projection device has at least one collimation element for collimating the at least one light beam emitted by the at least one light source. The

Collimating element is preferably arranged after the light source. Particularly preferably, the collimation element is arranged directly after the light source or the assembly containing the light source. This can

advantageously a collimated light beam can be obtained.

According to a preferred embodiment, the light source is arranged at a hinge-distal end of the at least one eyeglass temple. The hinge-distal end of at least one eyeglass temple is included

Proper use of the data glasses usually located at the user's ear. Among other things, this has the advantage of a more flexible spatial distribution of weight and volume. By this feature and the arrangement of a light guide between the hinge distal end of the eyeglass temple and the hinge near end of the eyeglass temple can be a spatial

Decoupling of light sources and in the beam path following optical

Elements are achieved. As a result, the individual optically relevant components of the system can be arranged independently of each other. Overall, the overall system can thus be realized less voluminous, lighter and in particular balanced. Consequently, both the wearing comfort and the aesthetics increase. Both points represent important sales arguments, particularly in the CE area. The spatial separation of the optical components makes it possible, among other things, to use a larger number of optical elements in the optical path, which can be accommodated directly in front of the micromirror both in the module of the light sources and in the beam path , Preference is given here micro-optics or integrated optics are used to fully exploit the potential advantages in terms of space, weight, cost, manufacturability, reproducibility and robustness. The above decoupling provides an optical path with space for a larger number of optically active surfaces and elements, an optical path with more options for preserving and shaping a desired beam profile, and an optical path with more favorable

Angle of incidence on the deflector, e.g. HOE, if used.

According to a preferred embodiment, the positioning device has a second deflecting element. This is arranged at a hinge near end of at least one eyeglass temple and deflects the light beam to the reflection element. The second deflecting element preferably has two reflective surfaces. Each reflective surface preferably deflects the light beam by 90 °. Preferably, the reflective surfaces are arranged at an angle of 90 °. More preferably, the second deflecting element is a prism. By the second deflecting element coming from the light source or the light module light beam can be advantageously deflected to the reflection element.

According to a preferred embodiment, the light beam is coupled into the light guide via a diffractive element. The diffractive element may be, for example, a grating or a hologram. This can be used to further reduce space by avoiding the dichroic mirror.

According to a preferred embodiment, the light guide is a part of the at least one eyeglass temple. Particularly preferably, the at least one eyeglass temple consists of the light guide. According to such an embodiment, the eyeglass temple can be designed as a light guide, that he a

Represents design element. For example, For example, the effect that occurs when light is poorly coupled into an optical fiber, that is, into the cladding rather than into the core, or when the fiber is severely curved and therefore not complete

Total reflection takes place more in its interior, used to make the temple look lit. This would make it widely visible that it is a data goggles, which could make them a status symbol for their owner, similar to an expensive new smartphone, could advance. In another embodiment, the light or waveguide may be configured For example, using appropriate grids or HOEs, they may display certain content, such as a manufacturer's logo or other designs. Thus, the manufacturer of the product would be widely recognizable and can achieve a direct advertising effect.

Due to the design freedom, the u. a. It is that the light source and other optically active elements in the optical path by using the optical fiber are arranged spatially approximately arbitrarily to each other, in particular can be separated from each other, the light source, which represents a large part of the required installation space volume, are mounted behind the ear, whereby the HMD less beefy and thus aesthetically pleasing effect. This results in more creative freedom in terms of appearance and fashionable aspects. This also increases the social acceptance of data glasses, as this is rather perceived as nice.

According to further preferred embodiments, the module with the

Light sources and the overlay optics behind the ear with the

Power supply of an audio device combined. The system is designed so that a power supply for audio device and the

Projection device is used.

Thus, in such a system, the two senses of seeing and of hearing are simultaneously addressed, thereby allowing a higher degree of immersion in an augmented reality.

According to a further embodiment, the projection device has three light sources for emitting a respective light beam, the three light sources each having different wavelengths. The three different wavelengths of the three light sources preferably form an RGB color space. The light source is preferably monochromatic or quasi monochromatic. An RGB color space is an additive color space that

Reproducing color perceptions by additive mixing of three primary colors (red, green and blue). The three different wavelengths are suitable for giving a user an impression of additive color mixing of a full-color image. This embodiment has the advantage that with these three A large part of the colors recognizable to humans can be projected.

The three light beams are preferably merged into a single light beam. To merge the light beams of the three light sources is preferably a light guide with diffractive coupling elements or are preferably used dichroic elements.

Before merging the light beams of the three light sources, wavelength-specific optics are preferably used for each light beam. After merging the light beams of the three light sources, wavelength-overlapping optics are preferably used for the merged light beam.

The invention further comprises a data glasses. This has a spectacle lens and a projection device described above, wherein the deflecting element is arranged on or in the spectacle lens.

Further advantages and embodiments of the invention will become apparent from the description and the accompanying drawings.

It is understood that the features mentioned above and those yet to be explained below can be used not only in the particular combination indicated, but also in other combinations or in isolation, without departing from the scope of the present invention.

Brief description of the drawings

Embodiments of the invention are illustrated in the drawings and are explained in more detail in the following description.

FIG. 1 shows a schematic representation of a projection apparatus according to an embodiment; and Figures 2 to 6 each show a schematic representation of a scanner optics of a projection device according to an embodiment.

Figure 7 shows a schematic representation of a data glasses according to an embodiment.

Embodiments of the invention

FIG. 1 shows the basic mode of operation of the projection device 100. The projection device 100 has a scanner optics 152 and a first

Deflection element 102, which is designed as a holographic element 103 in this embodiment. The holographic element 103 is at a

Eyeglass lens 402 attached, which in turn is attached to the eyeglass frame 120.

The scanner optics 152 has a light module 130, a light guide 124, a second deflection element 116 designed as a prism and a reflection element 112. The light module 130 has the light source 104 and a collimating element 114. The light module 130 is arranged at the hinge-distal end 119 of the eyeglass temple 118. The second deflecting element 116 is arranged at the hinge-near end 117 of the at least one spectacle arm 118.

The collimated light beam is coupled into the light guide 124. Since the second deflecting element 116 is monolithic with the light guide 124, the light beam continues to pass into the prism of the second deflecting element 116, is reflected there twice, changing its direction by 180 °, then leaves the second deflecting element 116 and then strikes the Reflection element 112, from where it is sent through an exit window 148 in the direction of the deflecting element 102. The deflected by the deflection element 102 light beam 106 then strikes an eye lens 108 of a user, from where the light beam 106 is focused on the retina 110 of an eyeball 107. The scanner optics 152 is arranged in a housing 105 fastened to the eyeglass frame 120 and to the eyeglass temple 118.

Different embodiments of the scanner optics 152 with housing 105 are shown in FIGS. 2 to 5. Figure 2 shows a scanner optics 152, which is taken in a housing 105. The scanner optics 152 forms together with the not shown

Deflection element 102 a projection device 100, as shown in Figure 1.

The scanner optics 152 with the housing 105 of Figure 2 differs from the corresponding scanner optics 152 with housing 105 of Figure 1 in that in the embodiment of Figure 2, three different light sources 104 are used with different wavelengths. The three

different light beams 106 emitted by the three light sources 104 each pass through a collimation element 114 and are then combined by means of two dichroic mirrors 150 into a merged beam 106, which is then collimated again by another collimating element 114. Thereafter, the light beam 106 is coupled into the light guide 124 as in FIG. The further beam path differs from Figure 1 except for the fact that optics adapted to the different light beams 104 are used.

The scanner optics 152 with the housing 105 of FIG. 3 differs from the corresponding scanner optics 152 with the housing 105 of FIG. 2 in that in the embodiment of FIG. 3 after the second deflection element 116 and the reflection element 112 a correction optics 132 is arranged. In the present case, the correction optics 132 are shown as a combination of two cylindrical lenses with longitudinal axes arranged perpendicular to one another. The correction optics 132 improves the symmetry and / or reduces the spot size of the light beam and has a non-rotationally symmetric optical element.

The correction optics 132 depicted in FIG. 3 are designed for three different wavelengths, namely those used by the light sources 104.

The scanner optics 152 with the housing 105 of FIG. 4 differs from the corresponding scanner optics 152 with the housing 105 of FIG. 2 in that, in the embodiment of FIG. 4, a correction optics 132 is arranged after the three collimating elements 114 of the three light sources 104. After the three collimation elements 114, the three light beams 106 are combined by means of two dichroic mirrors 150 into a merged beam 106. The further beam path does not differ from FIG. 2.

The scanner optics 152 with the housing 105 of Figure 5 differs from the corresponding scanner optics 152 with housing 105 of Figure 4, characterized in that in the embodiment of Figure 4 in that in the embodiment of Figure 5 after the second deflecting element 116 and the reflection element 112th a correction optics 132 is arranged. The remaining beam path does not differ from FIG. 4.

FIG. 6 shows a scanner optical system 152 for a polychromatic system, in which three light beams 106 with different wavelengths are coupled into a light guide 124 by means of three diffractive coupling elements 158. From the light guide 124, the light beam enters the executed as a prism second

Deflection element 116, which is designed monolithically with the light guide 124. After two internal reflection, which deflects the light beam 106 by 180 °, the light beam 106 again emerges from the second deflection element 116 and strikes the reflection element 112 and finally through the exit window 148 out of the housing 105.

FIG. 7 shows a schematic representation of a data goggle 400 with a projection device 100 according to one exemplary embodiment. The

Projection device 100 in this case has a scanner optics 152 and the

Deflection element 102 on. The scanner optics 152 is arranged in the housing 105 and transmits a light beam 106, not shown, through the appearance window 148 onto the deflection element 102. The data spectacle 400 has a spectacle lens 402 on which the deflection element 102 is arranged. For example, the deflecting element 102 is realized as part of the spectacle lens 402. Alternatively, the deflecting element 102 is realized as a separate element and connected to the spectacle lens 402 by means of a suitable joining method.

Claims

claims

1. Projection device (100) for a data goggle (400) with at least one eyeglass temple (118), wherein the projection device (100) has the following features:

at least one light source (104) for emitting at least one

Light beam (106);

at least one first deflecting element (102) arranged on or disposable on a spectacle lens (402) of the data goggles (400) for projecting an image onto a retina (110) of a user of the data goggles (400) by deflecting and / or focusing the at least one light beam (106 to an eye lens (108) of the user; and

at least one reflection element (112) for reflecting the light beam (106) onto the first deflection element (102);

marked by

a light guide (124) disposed between the light source (104) and the reflective element (112); and

in that the optical fiber is a single-mode or a single-mode optical fiber.

2. Projection device (100) according to claim 1, characterized in that the light guide (124) comprises an optical waveguide, a light guide cable or a photonic crystal.

3. projection device (100) according to claim 1 or 2, characterized

in that the light guide (124) is arranged along the at least one eyeglass temple (118).

4. Projection device (100) according to one of the preceding claims, characterized in that the light guide (124) is designed monolithic.

5. Projection device (100) according to one of the preceding claims, characterized by at least one collimation element (114) for

Collimating the at least one light beam (106) emitted by the at least one light source (104).

6. projection device (100) according to one of the preceding claims, characterized in that the light source (104) on a

hinge-distal end (119) of the at least one eyeglass temple (118) is arranged.

7. projection device (100) according to one of the preceding claims, characterized by a second deflecting element (116), which at a hinge near end (117) of the at least one eyeglass temple (118) is arranged, for deflecting the light beam (106) on the

Reflection element (112).

8. Projection device (100) according to one of the preceding claims, characterized in that the light beam (106) via a diffractive element (158) is coupled into the light guide (124).

9. projection device (100) according to one of the preceding claims, characterized in that the light guide (124) is a part of the at least one eyeglass temple (118).

10. Data glasses (400) with the following features:

a spectacle lens (402); and

a projection device (100) according to one of claims 1 to 9, wherein the first deflecting element (102) is arranged on or in the spectacle lens (402).