WO2014014411A1

WO2014014411A1 - Compact opto-electronic module and method for manufacturing the same

Info

Publication number: WO2014014411A1
Application number: PCT/SG2013/000283
Authority: WO
Inventors: Hartmut Rudmann; Markus Rossi
Original assignee: Heptagon Micro Optics Pte. Ltd.
Priority date: 2012-07-17
Filing date: 2013-07-09
Publication date: 2014-01-23
Also published as: TW201419505A

Abstract

The optical module (1) comprises - a first member (O) having a first face which is substantially planar, wherein directions perpendicular to said first face are referred to as vertical directions (z) and directions perpendicular to a vertical direction are referred to as lateral directions (x,y); - a second member (P) having a second face facing said first face, which is substantially planar and is aligned substantially parallel to said first face; - a third member (S) comprised in said first member (O) or comprised in said second member (P) or distinct from these, which comprises an opening (4), in particular wherein said third member is a unitary part; and - an optical element (30,32). The first member (O) comprises a transparent portion (t) through which light can pass, and said optical element (30,32) is attached to said first face or is comprised in said first member (O) at said first face. And said optical element (30,32) is spaced apart from said transparent portion (t) and located within said opening. Various optical arrangements can be realized this way in a miniscule optical package (1).

Description

COMPACT OPTO-ELECTRO IC MODULE AND METHOD FOR

MANUFACTURING THE SAME

Technical Field

The invention relates to the field of optics and more specifically to the packaging and l o manufacturing of optical or opto-electronic components. More particularly, it relates to optical modules and to methods of manufacturing the same and to appliances and devices comprising such modules. The invention relates to methods and apparatuses according to the opening clauses of the claims.

Definition of Terms

"Active optical component": A light sensing or a light emitting component. E.g., a photodiode, an image sensor, an LED, an OLED, a laser chip. An active optical component can be present as a bare die or in a package, i.e. as a packaged component.

"Passive optical component": An optical component redirecting light by refraction and/or diffraction and/or (internal and/or external) reflection such as a lens, a prism, a mirror, or an optical system, wherein an optical system is a collection of such optical components possibly also comprising mechanical elements such as aperture stops, image screens, holders.

"Opto-electronic module": A component in which at least one active and at least one passive optical component is comprised.

5 "Replication": A technique by means of which a given structure or a negative thereof is reproduced. E.g., etching, embossing, imprinting, casting, molding.

"Wafer": A substantially disk- or plate-like shaped item, its extension in one direction (z-direction or vertical direction) is small with respect to its extension in the other two directions (x- and y-directions or lateral directions). Usually, on a (non-blank) wafer, a l o plurality of like structures or items are arranged or provided therein, typically on a rectangular grid. A wafer may have openings or holes, and a wafer may even be free of material in a predominant portion of its lateral area. A wafer may have any lateral shape, wherein round shapes and rectangular shapes are very common. Although in many contexts, a wafer is understood to be prevailingly made of a semiconductor j 5 material, in the present patent application, this is explicitely not a limitation.

Accordingly, a wafer may prevailingly be made of, e.g., a semiconductor material, a polymer material, a composite material comprising metals and polymers or polymers and glass materials. In particular, hardenable materials such as thermally or UV-curable polymers are interesting wafer materials in conjunction with the presented invention.

20 "Lateral": cf. "Wafer"

"Vertical": cf. "Wafer"

"Light": Most generally electromagnetic radiation; more particularly electromagnetic radiation of the infrared, visible or ultraviolet portion of the electromagnetic spectrum. 5 Background of the Invention

In US 5,912,872, an integrated optical apparatus is presented. In the manufacture thereof, a support wafer having a plurality of active elements thereon is aligned with a transparent wafer having a corresponding plurality of optical elements. Such a support- transparent wafer pair may then be diced apart.

In US 2011/0050979 Al, an optical module for an electro-optical device with a functional element is disclosed. The optical module includes a lens substrate portion with at least one lens element, and a spacer. The spacer serves to keep the lens substrate at a well-defined axial distance from a base substrate portion of the fully assembled electro-optical device. In order to ensure an improved performance of the functional element, an EMC shield is provided. The spacer is at least in parts electrically conductive and thus forms the EMC shield or a part thereof. A method of manufacturing a plurality of such modules on a wafer scale is also disclosed in US 2011/0050979 Al. From US 6'314'223 Bl, a laser power monitor and system is known. Therein, a laser emits light through a substrate on which a diffractive element is present, the diffractive element reflecting a portion of the emitted laser light to a photodetector.

Summary of the Invention

It is one object of the invention to create an novel way of manufacturing optical modules or devices and/or to create novel optical modules or devices. In addition, appliances comprising a multitude of such optical modules or devices shall be provided. Another object of the invention is to provide particularly miniscule or compact or miniaturized optical modules or devices and/or to provide methods for manufacturing the same.

Another object of the invention is to provide a particularly fast way of manufacturing optical modules or devices.

Another object of the invention is to provide optical modules or device having particularly low manufacturing tolerances and a way of manufacturing such optical modules or devices with high precision.

Another object of the invention is to provide a way of mass-producing miniaturized optical modules or devices and to provide corresponding optical modules or devices.

The optical modules and/or devices can in particular be opto-electronic modules.

Further objects emerge from the description and embodiments below.

At least one of these objects is at least partially achieved by apparatuses and methods according to the patent claims.

The optical module comprises

— a first member having a first face which is substantially planar, wherein

directions perpendicular to said first face are referred to as vertical directions and directions perpendicular to a vertical direction are referred to as lateral directions;

— a second member having a second face facing said first face, which is

substantially planar and is aligned substantially parallel to said first face;

— a third member comprised in said first member or comprised in said second member or distinct from these, which comprises an opening, in particular wherein said third member is a unitary part; and

— an optical element; wherein said first member comprises a transparent portion through which light can pass, wherein said optical element is attached to said first face or is comprised in said first member at said first face, and wherein said optical element is spaced apart from said transparent portion and located within said opening.

5 Such an optical module is suitable for realizing, in a very compact manner, an optical system or arrangement which may have a considerable complexity. It is thereby possible to provide a packaged optical or opto-electronic component providing advanced functionalities. Furthermore, such optical modules can be mass-produced to tight tolerances, as will become clear from the description of the methods of

l o manufacturing described below.

Through said transparent area, light shall enter or exjt or both, enter and exit, said optical module, depending on the functionality realized in the optical module. Of course, it is possible to provide two or more transparent portions in one optical module.

Said first and second faces are usually pointing to the inside of the optical module.

15 Said third member usually is arranged between said first and second surfaces. It may be considered a spacer. Said third member can be provided for ensuring a well-defined distance between said first and second members and/or for ensuring a well-defined distance between said first and second faces. Said third member may alternatively or additionally be provided for ensuring a well-defined mutual (parallel) alignment of said 0 first and second faces.

Providing that said third member is a unitary part, can provide an enhanced

manufacturability.

Said third member may in particular be made of one single material, wherein this material may be a composite material, in particular a homogeneous composite material. 5 A polymer material can be particularly suitable for the third member.

In one embodiment, said optical element is encircled by said third member, in particular in at least one plane parallel to said first and second planes. In one embodiment which may be combined with the before-addressed embodiment, said optical element is at least one of

— a dispersive element, e.g., a prism or a diffraction grating (planar or curved; transmissive or reflective);

5 — an optical mirror, wherein planar as well as curved mirrors may be provided;

— a light emitter, e.g., an LED, an OLED, a laser, in particular a VCSEL;

— a light detector, e.g., a photo diode, a two-dimensional light sensor such as a pixel array, an arrangement of light detectors.

In one embodiment which may be combined with one or more of the before-addressed l o embodiments, said first and second members are interconnected, in particular directly interconnected (neglecting bonding material possibly present), by means of said third member. Usually, said first and second members are fixed with respect to each other via said third member.

In one embodiment which may be combined with one or more of the before-addressed 15 embodiments, outer bounds of a vertical silhouette of the module (i.e. the outer borders of a shape described by the optical module in a projection into a lateral plane) and outer bounds of a vertical silhouette of said first, second and third members (i.e. the outer borders of a shape described by the respective member in a projection into a lateral plane) each describe a substantially rectangular shape. This can effect an enhanced

0 manufacturability. In particular, all of the mentioned vertical silhouettes can describe one and the same rectangular shape. It can be provided that lateral dimensions of said first and second and third members are substantially identical. It is well possible to wafer-level manufacture such optical modules, which in turn can result in high- precision high-volume manufacturing. 5 In one embodiment which may be combined with one or more of the before-addressed embodiments, the optical module comprises an at least partially reflective element, e.g., an optical mirror or a reflection diffraction grating, and it may be planar or curved. Said at least partially reflective element is attached to said second face or is comprised in said second member at said second face, e.g., in form of a reflective coating. An at least partially reflective element can redirect light within the optical module so as to realize within the optical module an optical path having a lateral component, functionally (optically) interconnecting said transparent portion with said optical element, the optical path in particular comprising at least one first section on which light travels from the first to the second member and at least one second section on which light travels from the second to the first member, at least one of said sections having a lateral component. This can make possible to realize, within the optical module, optical systems similar to those realized in slab optics. The third member may be provided for ensuring a well- defined distance (in particular well-defined vertical distance) between said at least partially reflective element and said optical element and/or between said at least partially reflective element and said transparent portion.

Thus, in one embodiment referring to the last-addressed embodiment, said transparent portion, said at least partially reflective element and said optical element are mutually arranged in such a way that light passing through said transparent portion can propagate along a path interconnecting said transparent portion and said at least partially reflective element and interconnecting said at least partially reflective element and said optical element. Such an optical path has a lateral component and may be considered a folded optical path. Such a folded optical path may make possible to realize long optical path lengths within small lateral bounds, similarly as so-called slab optics does. In slab optics, light propagates in a piece of glass having two faces usually describing parallel flat areas, the light being multiply reflected hence and forth between these two faces due to total internal reflection. Slab optics can also, in a more general view, be considered integration of free-space planar optical components. Example for setups for slab optics can be found, e.g., in EP 0 674 192 A2 and in US 4 71 1 997.

In one embodiment referring to the last-addressed embodiment, said path comprises at least two path portions running along different directions, said different directions differing in their respective lateral components, in particular, said different directions differ substantially in their respective lateral components. In such embodiments, particularly long and/or particularly elaborate optical paths may be providable within the optical module, and it can make possible to achieve optical modules of particularly small form factor, at least considering its functionality. Instead of having light

5 propagate laterally basically along one direction only, one can make use of x and y directions. It is possible, in such embodiments, to provide

— that said at least two path portions are such path partions along which light propagates subsequently; or

— that said at least two path portions are such path partions along which light l o propagates simultaneously.

In the first case, it can, e.g., be provided that one or more reflective elements redirect a light beam in the optical module, so as to make the light inside the optical module propagate along a path along which x- and y-components change, e.g., a zigzag path. In the second case, it can, e.g., be provided that one or more diffractive elements divide a 25 light beam in the optical module into several light beams, the several light beams

running along directions having different x- and y-components.

In a particular aspect of the invention, the at least partially reflective element is provided, but said optical element is not. The provision of said optical element is accordingly optional. Specific embodiments of said particular aspect of the invention 0 can be construed from the embodiments described for the case that said optical element is provided.

In one embodiment which may be combined with one or more of the before-addressed embodiments, at least one of said first and second members, in particular both, said first and second members, are, at least in part, made substantially of an at least substantially 5 non-transparent material. Of course, said transparent portion is not made of an at least substantially non-transparent material. Such a choice of material can inhibit undesired exit of light out of the optical module and/or avoid that undesired light enters the optical module. It may contribute to optically sealing the optical module, wherein, of course, the optical sealing is interrupted by the transparent portion, in particular solely thereby.

In one embodiment which may be combined with one or more of the before-addressed embodiments, said third member is, at least in part, made substantially of an at least substantially non-transparent material. Such a choice of material can inhibit undesired exit of light out of the optical module and/or avoid that undesired light enters the optical module. It may contribute to optically sealing the optical module.

In one embodiment which may be combined with one or more of the before-addressed embodiments, said first, second and third members are of generally block- or plate-like shape, possibly comprising at least one hole. A wafer-level manufature of such optical modules may be well possible.

In one embodiment which may be combined with one or more of the before-addressed embodiments, said first and second members substantially is a printed circuit board or a printed circuit board assembly. At least one electrical connection across itself may thus be provided in said first member and/or said second member. Thus, an electrical connection from an electronic or active optical component comprised in the optical module to the outside of the optical module can be realized, the electrical connection vertically traversing the respective member. This can provide a high degree of integration and functionality in the optical module. In one embodiment which may be combined with one or more of the before-addressed embodiments, said third member is at least one of made of a hardened hardenable material and obtained using a replication process. This can make possible to achieve an enhanced manufacturability. This can make possible to provide third members in form of unitary parts in an efficient way. In one embodiment which may be combined with one or more of the before-addressed embodiments, said optical element is at least one of made of a hardened hardenable material and obtained using a replication process. This can make possible to achieve an enhanced manufacturability. In one embodiment which may be combined with one or more of the before-addressed embodiments, said optical element is a passive optical component. In particular, it may be an at least partially reflective element. Alternatively, the optical element is an active optical component. In this latter case, it may in particular be a light emitting element or 5 a light detecting element.

In one embodiment which may be combined with one or more of the before-addressed embodiments, said first member comprises a non-transparent blocking portion. In such a blocking portion, light cannot traverse the first member. In particular, it can be provided that said transparent portion is surrounded by said blocking portion. It can in particular i o be provided that said first member is substantially composed of one or more blocking portions and one or more transparent portions, wherein it may be provided that each transparent portion is surrounded (in particular laterally surrounded) by at least one blocking portion.

In one embodiment which may be combined with one or more of the before-addressed 25 embodiments, said transparent portion is substantially made of a transparent material, in particular of a hardened hardenable material, e.g., of a curable material such as a curable epoxy resin. The transparent portion may be substantially made of a solid transparent material. Alternatively, said transparent portion can substantially be an opening (a hole).

In one embodiment which may be combined with one or more of the before-addressed 0 embodiments, said transparent portion comprises a passive optical component, in

particular an optical structure. Such an optical structure can in particular be or comprise a lens, a lens element, a prism, a transmission diffraction grating. An optical structure forming a grating and a lens or a grating and a mirror can also be provided. Such an optical structure can be capable of, e.g., dividing light into beams propagating along 5 different paths and at the same time focussing the light.

In one embodiment which may be combined with one or more of the before-addressed embodiments, the optical module comprises a second optical element attached to said second face or comprised in said second member at said second face. In this case, the earlier mentioned optical element can in particular be a second at least partially reflective element. And it is possible to provide that said second optical element is a passive optical component, in particular an at least partially reflective element, or that said second optical element is an active optical component, in particular a light emitting element or a light detecting element. Various functionalities known from slab optics can this way be implemented in the optical module.

In one embodiment which may be combined with one or more of the before-addressed embodiments, a number of at least partially reflective elements is comprised in the optical module which are arranged such that light propagating within the optical module from said transparent portion to said optical element or vice versa travels along an optical path having at least three sections interconnecting the first and the second member, at least one, in particular each of the at least three sections having a lateral component. And typically, on each of said at least three sections, the light travels within the third member.

In one embodiment which may be combined with one or more of the before-addressed embodiments, the optical module comprises an inside volume and a housing enclosing said inside volume, said housing being, except for said transparent portion, completely non-transparent, such that light can enter or exit said inside volume solely through said transparent portion or, if at least one additional transparent portion is provided, through said transparent portions. More particularly, it can be provided that said first, second and third members contribute to said housing, and it can even more particularly be provided that said first, second and third members form said housing. Said inside volume usually is comprised in said opening. Thus, a very compact packaged optical module, e.g., opto-electronic module, can be realized. And the optical module can be realized using a very small number of parts only.

In one embodiment which may be combined with one or more of the before-addressed embodiments, the module forms a first and a second channel, said first channel comprising said optical element, said module comprising an active optical component, said active optical component being comprised in said second channel. In particular, it can be provided that said optical element is an additional active optical component. Even more particularly, one of said active optical components is a detecting member, and the other an emission member. Usually, such modules comprise a channel separator 5 by means of which said first and second channels are optically separated from each other within the module.

It is to be noted that it is possible to provide optical modules which do not comprise any active optical component. And it is also possible to provide optical modules which do not comprise any printed circuit board or printed circuit board assembly. Such "passive" l o optical modules can be useful, e.g., in or as optical communication devices, or they do imaging, e.g., like a microscope or telescope or binoculars; or they could let escape light of certain colors only (upon light entering the module).

The appliance according to the invention comprises a multitude of optical modules according to the invention. Such an appliance can in particular be a wafer stack, such as 15 a wafer stack used during manufacture of the optical module, e.g., comprising a first wafer comprising a multitude of first members, a second wafer comprising a multitude of second members and third wafer comprising a multitude of third members.

The method for manufacturing a device comprises the step of a) providing a first wafer comprising a multitude of transparent portions through 0 which light can pass;

b) providing a multitude of optical elements;

wherein each of said multitude of optical elements is attached to said first wafer or is comprised in said first wafer, and wherein each of said multitude of optical elements is spaced apart from any of said multitude of transparent portions. 5 In one aspect of the invention, the device is said first wafer; in another aspect, said

device is an optical module; in another aspect of the invention, said device comprises, in addition to other parts, an optical module. The method can be used for manufacturing a device according to the invention.

Usually, each of said multitude of optical elements is allocated with a transparent portion of said multitude of transparent portions.

Because of the transparent portions, light can pass through the first wafer. Light can traverse the first wafer through said transparent portions. The optical elements can have the properties described above in conjunction with the optical modules.

In one embodiment of the method, the method comprises at least one of the step of nl) manufacturing said first wafer using a replication process, in particular

embossing. This way, i.e., when a replication step is carried out for or during manufacturing said first wafer, a high-precision mass production can be accomplished.

In one embodiment of the method, which may be combined with the before-addressed embodiment, the method comprises the step of k) manufacturing each optical element of said multitude of optical elements using a replication process, in particular embossing.

Replication and in particular embossing can make possible to manufacture a high number of tiny parts in high precision in mass production.

In an exemplary replication process as it may be applied in any case where in the present patent application a replication process is mentioned, a structured surface is embossed into a liquid, viscous or plastically deformable material, then the material is hardened, e.g., by curing using ultraviolet radiation and/or heating, and then the structured surface is removed. Thus, a replica (which in this case is an negative replica) of the structured surface is obtained. Suitable materials for replication are, e.g., hardenable (more particularly: curable) polymer materials or other replication materials, i.e. materials which are transformable in a hardening step (more particularly in a curing step) from a liquid, viscous or plastically deformable state into a solid state. Replication is a known technique, cf., e.g., WO 2005/083789 A2 for more details about this.

In one embodiment which may be combined with one or more of the before-addressed method embodiments, the method comprises the step of m) manufacturing each transparent portion of said multitude of transparent portions using a replication process, in particular using embossing.

Note that the wording "manufacturing ... using" a certain step or process (such as a replication process) does here and in general not exclude the provision of additional manufacturing steps or processes during the manufacture.

In one embodiment which may be combined with one or more of the before-addressed method embodiments, the method comprises the step of c) providing a second wafer;

d) providing a third wafer, wherein said third wafer is comprised in said first wafer or is comprised in said second wafer or is distinct from these, and wherein said third wafer comprises a multitude of openings; and

e) forming a wafer stack by stacking said first, second and third wafers, such that said third wafer is arranged between said first and second wafers and that each of said multitude of optical elements is allocated with an opening of said multitude of openings.

This way, optical devices according to the invention can be manufactured in an efficient way. Usually, each of said multitude of optical elements is arranged within one of said multitude of openings. And, usually, each of said multitude of openings is allocated with a transparent portion of said multitude of transparent portions and allocated with an optical element of said multitude of optical elements.

Note that the device can be said wafer stack, but the device can also be an optical module or a device comprising, among others an optical module. In one embodiment referring to the last-addressed embodiment, step e) comprises a bonding step, e.g., a gluing step, and in particular using a polymer material or a hardenable material. More particularly, step e) may comprise applying and hardening an epoxy resin, or even more particularly a radiation-curable epoxy resin. In one embodiment referring to one or both of the two last-addressed embodiments, the method comprises at least one of the steps of n2) manufacturing said second wafer using a replication process, in particular

embossing; n3) manufacturing said third wafer using a replication process, in particular

embossing.

This way, i.e., when a replication step is carried out for or during manufacturing one or both of these wafers, a high-precision mass production can be accomplished.

In one embodiment which may be combined with one or more of the before-addressed method embodiments, said second wafer comprises a multitude of at least partially reflective elements.

In one embodiment which may be combined with one or more of the before-addressed method embodiments comprising steps c), d) and e), the method comprises the step of f) separating said wafer stack into said multitude of devices, in particular into a multitude of optical modules, more specifically of opto-electronic modules. In particular, each of said devices comprises

— at least one of said multitude of transparent portions;

— at least one of said multitude of optical elements; and

— at least one of said multitude of openings.

In particular, said device manufactured using the method is one of said optical or opto- electronic modules. Said separating can be accomplished using known dicing techniques, e.g., sawing, laser cutting and others.

The invention comprises device with features of corresponding methods according to the invention, and, vice versa, also methods with features of corresponding devices 5 according to the invention.

The advantages of the devices basically correspond to the advantages of corresponding methods, and, vice versa, the advantages of the methods basically correspond to the advantages of corresponding devices.

The method for manufacturing a device comprising an optical module comprises i o manufacturing said optical module using one of the above-mentioned methods, in

particular

— wherein said device comprises an optical module according to the invention; and/or

— wherein said device comprises a printed circuit board on which said optical 15 module is mounted, wherein, more particularly, the device comprises a

processing unit operationally connected to said optical module.

The device comprises an optical module, wherein said optical module is an optical module as described above, in particular said device may comprise a printed circuit board on which said optical module is mounted. 0 The device can be, e.g., a smart phone, a photographic device, an optical sensor, an optical communication device. Under "optical communication device", we understand an optical compontent for use in optical data transmission, more particularly in optical digital data transmission, even more particularly in data transmission for optical telecommunication. Usually, an optical communication device has at least one input 5 port for receiving light and at least one output port for outputting light. And typically, in the optical communication device, some processing is applied to inputted light, which may be at least one of amplifying, focussing, defocussing, filtering, optical filtering, separating, dividing, splitting, merging.

Various apparatuses and methods have been described above. It can be said that the optical module interacts with the outside world. E.g, it can react to light entering the 5 optical module, e.g., producing signals depending on light entering the optical module.

And/or it can emit light, e.g., the emitted light having specifically tailored properties, or light entering the optical module as a consequence of the emission of the light can in turn be analyzed in the optical module, e.g., for producing signals depending on a result of said analysis. In a miniscule optical package, in particular in a miniscule opto- l o electronic package, a full optical system comprising a complicated optical path and several active and/or passive optical components may be comprised. Active optical components comprised in the optical module (which in this case is an opto-electronic module) may be provided, e.g., as bare dies or as chip-scale packages. The possibility to do so allows to realize particularly small package sizes.

15 Further embodiments and advantages emerge from the dependent claims and the

figures.

Brief Description of the Drawings 0

Below, the invention is described in more detail by means of examples and the included drawings. The figures show in a schematized manner:

Fig. 1 a cross-sectional view of a device comprising an optical module;

Fig. 2 various cross-sectional views of constituents of the optical module of 5 Fig. 1; Fig. 3 a cross-sectional view of wafers for forming a wafer stack for manufacturing a multitude of optical modules of Fig. 1 ;

Fig. 4 a cross-sectional view of a wafer stack for manufacturing a multitude of optical modules of Fig. 1 ;

5 Fig. 5 a cross-sectional view of an optical module on a printed circuit board;

Fig. 6 a cross-sectional view of an optical module comprising a diffraction grating;

Fig. 7 a view onto a vertical cross-section through the embodiment of Fig. 6 in a particular interpretation; l o Fig. 8 an illustration of a lateral view of an optical module;

Fig. 9 an illustration of a vertical cross-section through the optical module of

Fig. 8 in a first interpretation;

Fig. 10 an illustration of a vertical cross-section through the optical module of

Fig. 8 in a second interpretation;

15 Fig. 11 an illustration of a lateral view of an optical module;

Fig. 12 an illustration of a vertical cross-section through the optical module of

Fig. 11;

Fig. 13 an illustration of a vertical cross-section through the optical module of

Fig. 1 1; 0 Fig. 14 an illustration of a vertical cross-section through the optical module of

Fig. 1 1 ;

Fig. 15 a cross-sectional view of a device comprising an optical module.

The described embodiments are meant as examples and shall not confine the invention. Detailed Description of the Invention

Fig. 1 shows a schematic cross-sectional view of a device 10 comprising an optical module 1, wherein the optical module in particular is an opto-electronic module 1. The illustrated cross-section is a vertical cross-section. Fig. 2 shows various lateral schematic cross-sectional views of constituents of the module of Fig. 1, wherein the approximate positions of these lateral cross-sections are indicated in Fig. 1 by si to s5 and dotted lines. For s4 and s5, the direction of view is indicated by arrows.

Device 10 can be, e.g., an electronic device and/or a photographic device. It comprises, besides module 1, a printed circuit board 9 on which module 1 is mounted. In addition mounted on printed circuit board 9 is an integrated circuit 8 such as a control unit 8 or controller chip which is operationally interconnected with module 1 by printed circuit board 9. E.g., integrated circuit 8 may evaluate signals outputted by module 1 and/or provide signals to module 1 for controlling the same.

Module 1 comprises several constituents (P, S, O, B) stacked upon each other in a direction through which the term "vertical" is defined; it corresponds to the z direction (cf. Fig. 1). Directions in the x-y plane (cf. Fig. 2) perpendicular to the vertical (z) direction are referred to as "lateral".

Module 1 comprises a substrate P, a separation member S (which can also be referred to as spacer), an optics member O and an optional baffle member B stacked upon each other. Substrate P is, e.g., a printed circuit board assembly, but might be merely a printed circuit board. The printed circuit board (PCB) of this PCB assembly can more specifically also be referred to as an interposer. On the PCB, an active optical component 20 such as a light emitter 22 is mounted and a passive optical component 30, too. Passive optical component 30 can more specifically be a reflective element 33, e.g., a mirrored prism. On or at optics member O, a passive optical component 30 is arranged which more specifically is a reflective element 32, e.g., a curved mirror. Electrical contacts of active optical component 20 are electrically connected to the outside of module 1 by and via substrate P, where solder balls 7 are attached. Instead of providing solder balls 7, it would also be possible to provide contact pads on the PCB which are not (or at a later time) provided with solder balls. This way, module 1 can be mounted on printed circuit board 9, e.g., in surface mount technology (SMT), next to other electronic components such as controller 8. Module 1 is particularly suitable for an application in a compact electronic device 10 such as in a hand-held communication device, because it can be designed and manufactured to have a particularly small size. Separation member S has an opening 4 in which the active and passive optical components, respectively (22, 32, 33), are arranged. This way, these items are laterally encircled by separating member S (cf. Figs. 1 and 2).

Separation member S may fulfill several tasks. It can ensure a well-defined distance between substrate P and optics member O (through its vertical extension) which helps to achieve well-defined light paths within the module. Separation member S can also inhibit the propagation of light generated by active optical component 20 out of module 1 via undesired light paths. This is accomplished by separation member S forming a portion of the outside walls of module 1, separation member S being, e.g., made substantially of a non-transparent material. Typically, separating member S is made of a polymer material, in particular of a hardenable or, more specifically, curable polymer material, e.g., of an epoxy resin. If separating member S is made of a substantially non-transparent curable material, it can in particular be a heat-curable material.

Optics member O comprises a blocking portion b and a transparent portion t, the latter for allowing light emitted by active optical component 20 to leave module 1.

Blocking portion b is substantially non-transparent for light, e.g., by being made of a suitable (polymer) material, e.g., like described for separating member S. Transparent portion t comprises a passive optical component L or, more particularly and as an example, a lens member L, for light guidance. Lens member L may, e.g., comprise, as shown in Fig. 1, a lens element 5 in close contact to a transparent element 6.

Transparent element 6 can have the same vertical dimension as optics member O where it forms blocking portion b, such that optics member O where it forms blocking portion b together with transparent element 6 describes a (close-to-perfect) solid plate shape. Lens element 5 redirects light by refraction (cf. Fig. 1) and/or by diffraction (not illustrated in Fig. 1). Lens element 5 may, e.g., be of generally convex shape (as shown in Fig. 1), but lens element 5 may be differently shaped, e.g., generally or partially concave. It is furthermore possible (not shown) to provide another optical structure on the opposite side of transparent element 6.

Baffle member B is optional and allows to shield undesired light, in particular light leaving module 1 in an desired angle. Usually, baffle member B will have a transparent region 3 which may be embodied as openings or by means of transparent material. Baffle member B can, outside transparent region 3, be made of a material substantially attenuating or blocking light, or it could be provided with a coating having such a property, wherein the latter will usually be more complex to manufacture. The shape of baffle member B or, more precisely, of the transparent region 3, can, of course, be different from what is shown in Figs. 1 and 2, and it may, e.g., describe a cone-like shape or a truncated pyramid.

The lateral shape not only of the transparent regions 3, but also of the transparent portions t and of the openings 4 do not have to be like drawn in Fig. 2, but may have other appearances, e.g., polygonal or rectangular with rounded corners or elliptic.

Coming back to separation member S, it does not solely comprise laterally defined regions in which separation member S extends vertically to a maximum extent, namely tothe extent substantially defining the vertical distance between substrate P and optics member O, and to laterally defined regions in which it is completely free of material forming an opening vertically fully traversing said maximum vertical extension. But there is a region in which (usually non-transparent) material of separation member S extends vertically along only a portion of said maximum vertical extension, namely in the region of spacer portion Sb. Thus, spacer portion Sb can function as a light shield for light inside module 1 (cf. Fig. 1). It can prevent a propagation of light along undesired paths. In particular if separation member S is manufactured using replication, the extra functionality of separation member S provided by spacer portion Sb is readily 5 achieved, at nearly no cost in terms of manufacturability and manufacturing steps.

Instead of being a light-emitting module 1 comprising a light emitting member 22 as an active optical component 20, it could also be provided that active optical component 20 is a detection member for detecting light, such as an image detector or a photo diode. In this case, separation member S could also be provided for protecting the detection l o member from light that is not supposed to be detected by the detection member, by being substantially non-transparent and by forming a portion of the outside walls of module 1 and, if provided by forming a light shield by spacer portion Sb. And furthermore, transparent portion t could then be provided for allowing light to enter module 1 from the outside of module 1 and reach the detecting member.

25 And, it is also possible to provide, in one module 1, a light emitting member and a

detection member (not illustrated). Both would usually, for accomplishing electric contacts of these active optical components to the outside of module 1 , be mounted on a substrate P. Such a module could be used, e.g., for investigating the environment of module 1 by emitting light out of module 1 and detecting light having interacted with an 0 object in the environment of module 1.

And furthermore, it is possible to provide modules which are designed according to the same principles as discussed above, but comprising, in addition to one or two active optical components, one or more additional electronic components such as additional light detectors, and/or one or more integrated circuits, and/or two or more light sources. 5 Module 1 is an opto-electronic component, more precisely a packaged opto-electronic component. The vertical side walls of module 1 are formed by items P, S, O and B. A bottom wall is formed by substrate P, and a top wall by baffle member B or by baffle member B together with optics member O, or, in case no baffle member B is provided, by optics member O alone.

As is well visible in Fig. 2, the four items P, S, O, B, which can for the reasons above also be referred to as housing components (contributing to a housing of module 1), all 5 have substantially the same lateral shape and lateral dimensions. This is related to a possible and very efficient way of manufacturing such modules 1 which is described in more detail below referring to Figs. 3 and 4. These housing components P, S, O, and B are all of generally block- or plate-like shape or, more generally, of generally rectangular parallelepiped shape, possibly having holes or openings (such as baffle l o member B and separation member S do) or (vertical) projections (such as optics

member O does due to optical structure 5).

Passive optical components 32 and 33 and active optical component 22 are arranged such that light can propagate inside module 1 along an optical path interconnecting these components and transparent portion t. Transparent portion t being arranged

25 separate from optical element 32 (passive optical component 30,32) provides that said optical path has a lateral component (along the x direction).

Active electronic components 20 comprised in a module 1 (such as emission member 22 in the example of Fig. 1) can be packaged or unpackaged electronic components. For contacting substrate P, technologies such as wire-bonding or flip chip technology or any 0 other known surface mount technologies may be used, or even conventional through- hole technology. Providing active optical components as bare dice or chip scale packages allows to realized particularly small designs of modules 1 , yet also active optical components packaged in a different way may be comprised in a module 1.

Fig. 3 shows a schematical cross-sectional view of wafers for forming a wafer stack 2 5 for manufacturing a multitude of modules as shown in Figs. 1 and 2. It is possible to manufacture such modules 1 (practically) completely on wafer-scale, of course with a subsequent separation step. Although Figs. 3 and 4 only show provisions for three modules 1 , there will usually be in one wafer stack provisions for at least 10, rather at least 30 or even more than 50 modules in each lateral direction. Typical dimensions of each of the wafers are: laterally at least 5 cm or 10 cm, and up to 30 cm or 40 cm or even 50 cm; and vertically (measured with no components arranged on substrate wafer PW) at least 0.2 mm or 0.4 mm or even 1 mm, and up to 6 mm or 10 mm or even

5 20 mm.

Four wafers (or, with no baffle wafer provided: three wafers) are sufficient for manufacturing a multitude of modules as shown in Fig. 1 : A substrate wafer PW, a spacer wafer SW, an optics wafer OW and optional baffle wafer BW. Each wafer comprises a multitude of the corresponding members comprised in the corresponding i o module 1 (cf. Figs. 1 and 2), usually arranged on a rectangular lattice, typically with a little distance from each other for a wafer separation step.

Substrate wafer PW can be a PCB assembly comprising a PCB of standard PCB materials such as FR4, provided with solder balls 7 on the one side and with one or more optical elements (in Fig. 1 : active optical component 22 and passive optical

15 component 32) connected (e.g., soldered or glued) to the other side. The optical

elements can be placed on substrate wafer PW, e.g., by pick-and-place using standard pick-and-place machines. Similarly, passive optical component 32 may be placed on optics wafer OW.

When optical elements are provided on a wafer, it is important to ensure that they are 0 sufficiently accurately positioned with respect to each other.

In order to provide maximum protection from undesired light propagation, all wafers PW, SW, OW, BW can substantially be made of a material substantially non- transparent for light, of course except for transparent areas such as transparent portions t and transparent regions 3. 5 Wafers SW and BW and possibly also all or a portion of wafer OW may be produced by replication or at least using replication. In an exemplary replication process, a structured surface is embossed into a liquid, viscous or plastically deformable material, then the material is hardened, e.g., by curing using ultraviolet radiation or heating, and then the structured surface is removed. Thus, a replica (which in this case is an negative replica) of the structured surface is obtained. Suitable materials for replication are, e.g., hardenable (more particularly curable) polymer materials or other replication materials, i.e. materials which are transformable in a hardening step (more particularly in a curing 5 step) from a liquid, viscous or plastically deformable state into a solid state. Replication is a known technique, cf., e.g., WO 2005/083789 A2 for more details about this.

In case of optics wafer OW, replication or molding may be used for obtaining the non- transparent portion (blocking portion b). It would also be possible to provide holes, where transparent portions t are supposed to be, by drilling or by etching.

l o Subsequently, a so-obtained precursor wafer substantially comprised of blocking

portion b is provided with lens members L and passive optical component 22. The former may be accomplished by means of replication, e.g., forming lens members L as a unitary parts, e.g., as described in US 2011/0043923 Al. The lens members L can, however, also be manufactured starting from a semi-finished part being a wafer

15 comprising transparent elements 6 within holes by which transparent regions 3 are

defined. This can be particularly useful when the lens members L each describe at least one apex, and those apices are located outside a vertical cross-section of the optics wafer OW. Such a semi-finished part is (usually and in the exemplary case shown in the figures) a flat disk-like wafer having no holes penetrating the wafer in the transparent 0 regions 3 and having virtually no or only shallow surface corrugations, such surface corrugations usually being concave, i.e. not extending beyond the wafer surface as described by the blocking portions b.

A semi-finished part like that can be obtained starting from a flat precursor wafer (typically made of a single possibly composed material) having holes or openings where 5 the transparent portions t are supposed to be and then filling the holes with transparent material, e.g., using a dispensing process, and either filling the holes in the precursor wafer one-by-one, e.g., using a dispenser such as used for underfilling processes in flip- chip technology or the like, or by filling several holes at once, e.g., using a squeegee process (e.g., as known from screen printing) or a dispenser with several hollow needles outputting material. During the dispensing, the wafer can be placed on a flat support plate, e.g., made of a silicone. Care has to be taken in order to prevent the formation of air bubbles or cavities in the dispensed material, since this would degrade the optical properties of the lens members L to be produced. E.g., one can carry out the dispensing 5 in such a way that wetting of the wafer material starts at an edge formed by the wafer and an underlying support plate (or in a place close to such an edge), e.g., by suitably guiding a hollow needle outputting the material close to such an edge. Subsequently, the dispensed material is cured, e.g., by heat or UV radiation, so as to obtain hardened transparent material.

l o Convex meniscuses possibly formed this way can be flattened by polishing, so as to obtain a transparent element 6 having parallel surfaces adjusted to the wafer thickness. Then, by means of replication, optical structures 5 (lens elements 5) are applied to one or both sides (top and button side) of wafer OW. In case of concave meniscuses of the transparent elements, the replication can take place on these, wherein the amount of

15 applied replication material might have to be adjusted accordingly.

It is generally possible to provide that said spacer wafer SW and/or said baffle wafer BW are obsolete in the sense that a particular kind of optics wafer is provided which comprises one or both of these wafers, i.e. in this case, the respective wafer is or respective wafers are a portion of optics wafer. Such an optics wafer ("combined optics 0 wafer") incorporates the features and functionalities of said spacer wafer SW and/or of said baffle wafer BW. Producing such a "combined optics wafer" may be accomplished using a particular precursor wafer and, manufactured based thereon, a particular semifinished part. Such a precursor wafer and semi-finished part, respectively, has at least one structured surface, usually having protrusions extending vertically beyond at least 5 one of the two surfaces of transparent elements to be provided in the precursor wafer and present in the semi-finished part, respectively. Looking upon wafers OW and SW (or wafers OW and BW, or wafers OW and SW and BW) in Fig. 4 as one single part, it can be readily visualized what a corresponding optics wafer ("combined optics wafer") for manufacturing a module according to Fig. 1 and also a corresponding semi-finished part would look like.

In general, it is also, as a partial alternative to the above, possible to provide that spacer wafer SW is a portion of substrate wafer PW. In this case, substrate wafer PW would rather not be made of standard PCB materials, but of a replication material.

In order to form a wafer stack 2, the wafers are aligned and bonded together, e.g., by gluing, e.g., using a heat-curable epoxy resin. It is usually a critical point to ensure that each optical element on substrate wafer SW (such as active optical component 22 and passive optical component 33) is sufficiently accurately allocated with the optical elements of optics wafer OW (such as passive optical component 32) and transparent portion t.

Fig. 4 shows a cross-sectional view of a so-obtained wafer stack 2 for manufacturing a multitude of modules 1 as shown in Fig. 1. The thin dashed rectangles indicate where separation takes place, e.g., by means of using a dicing saw or by laser cutting.

The fact that most alignment steps are carried out on wafer level makes it possible to achieve a good alignment of the optical elements in a rather simple and very fast way. Thus, a well-defined optical path can be realized for light inside module 1. The overall manufacturing process is very fast and precise. Due to the wafer-scale manufacturing, only a very small number of production steps is required for manufacturing a multitude of modules 1.

Following the before-presented ideas, various other optical modules 1 may be construed and manufactured. In the following, some examples are described.

Fig. 5 shows a cross-sectional view of an optical module 1 on a printed circuit board 9. In contrast to the module of Fig. 1, the transparent portion t is not provided in optics member O, but in substrate member P. Being mounted on PCB 9, a through-hole 19 is provided therein so as to allow light to enter (or exit) module 1 therethrough and through transparent portion t. Through-hole 19 can function as a baffle, limiting the angular range under which light can enter module 1. Due to the (according to optical standards) very limited positioning accuracy achievable by mounting on a PCB, through-hole 19 will usually be designed to have a larger lateral extension than transparent portion t has.

Furthermore, another possible variant for transparent portion t is illustrated in Fig. 5. In the illustrated case, transparent portion t is merely an opening in housing 1 1 of module 1. A transparent element like transparent element 6 in Figs. 1 to 4 could also be provided in transparent portion t; this would contribute to avoid that undesired particles like dust could enter module 1. Like in the example of Figs. 1 to 4, the housing 1 1 of module 1 is substantially constituted by the comprised members O, S, P (in Figs. 1 to 4 also the optional member B).

Active optical component 25 of module 1 of Fig. 5 can be, e.g., a pixel array, e.g., an image sensor. Passive optical component 30 can, e.g., be an optical grating on a prism. Spacer portion Sb can contribute to preventing the detection by active optical component 25 of stray light entering module 1 in undesired ways. This way, module 1 of Fig. 5 can be used, e.g., for spectrally analyzing light entering the module. Via solder balls 7, signals obtained by active optical component 25 can be fed to an evaluation unit operationally interconnected to PCB 9, e.g., to an integrated circuit like item 8 in Fig. 1.

In a different interpretation of Fig. 5, active optical component 20 is a light emitter, and passive optical component 30 is a reflective element. In this case, module 1 could be a projector for projecting images. E.g., light emitter 20 would be a multi-pixel light emitter generating a full image frame at a time, and passive optical component 30 would be a mirror. But it could also be provided that light emitter 20 produces only one pixel or a portion of a full frame at a time, and item 30 would be a digital micromirror device creating a full image by subsequently guiding light emitted by light emitter 20 to different directions. In any of these cases, one or more lenses in transparent portion t might allow to achieve an improved image quality. Another optical module 1 is illustrated in Fig. 6 in a cross-sectional view. Therein, transparent portion t comprises a lens member L comprising a transparent element 6 to which on two opposing sides a lens element 5 each is attached, e.g., manufactured by replication on wafer level. On substrate member P, an arrangement 26 of photo diodes is arranged, e.g., in a linear arrangement. Furthermore arranged on substrate P are three passive optical components 30, 3 , 3 ". Passive optical component 30 is a reflection diffraction grating 36, and passive optical components 31 ', 3 Γ" are embodied as optical mirrors. Grating 36 may be manufactured using replication, in particular on wafer level, or it may be a (pre-fabricated) grating placed on substrate P, e.g., by pick- and-place. On optics member O, three passive optical components 31, 31", 31"" are arranged which are embodied as optical mirrors.

The mirrors (or at least a portion thereof) may be pre-fabricated mirrors placed on the respective member, e.g., by pick-and-place, or may be realized by applying a coating to the respective member (O and P, respectively). Light entering module 1 (through transparent portion t) can propagate along a light path passing, in this order, grating 36, mirrors 31, 3Γ, 31", 3 ", 31"" and detector arrangement 26. Several spacer portions, namely Sb, Sb\ Sb", Sb"\ Sb"", block stray light from propagating towards detecting arrangement 26. In a first way of interpreting Fig. 6, the optical components shown in Fig.6 are arranged substantially along one common x-z-plane. In this case, the optical module 1 shown in Fig. 6 will usually be of rather elongated shape, its extension in the y direction making up for only a fraction of its extension in the x direction (cf. the symbolic coordinate system in the bottom left corner of Fig. 6). The light path described by light propagating inside optical module 1 substantially runs along the x direction. It is, however, also possible to make specific use also of the y direction, as is exemplarily shown in Fig. 7. Fig. 7 shows a view onto a vertical cross-section through the embodiment of Fig. 6 in a second interpretation. The dotted line and the open arrow in Fig. 6 indicate where approximately said cross-section is taken. In this particular interpretation of the embodiment illustrated in Fig. 6, the light path described by light propagating inside optical module 1 has substantial components in both, the x direction and the y-direction. This way, rather long path lengths of the light path along which light propagates inside optical module 1 can be achieved. And various ways of shaping a light beam inside optical module 1 can thus be realized.

As is illustrated, too, in Fig. 7, it is also possible to choose virtually any suitable extensions of the spacer portions Sb, Sb', Sb",... along the y-axis. But with the vertical extension like shown in Fig. 6, the extension along the y-axis of the spacer portions Sb, Sb', Sb",... could also fully traverse the extension along the y-axis of opening 4 (unlike shown in Fig. 7). And, vice versa, provided an extension along the y-axis of the spacer portions Sb, Sb', Sb",... as illustrated in Fig. 7, the extension along the z-axis of the spacer portions Sb, Sb', Sb",... could also fully traverse the vertical extension along the z-axis of opening 4 (unlike shown in Fig. 6). Of course, in general, and for any embodiment, not only rectangular shapes are possible for spacer portions such as spacer portions Sb, Sb', Sb' ',..., but many more, such as, e.g., wedge shapes and angled shapes.

Fig. 8 is an illustration of a lateral view of another optical module 1 in which both lateral directions are made use of, more particularly in which light propagation inside the optical module 1 takes place along not only one lateral direction, but has substantial components along both lateral directions (x and y). More particularly, in Fig. 8, light having entered optical module 1 through transparent portion t is diffracted at a diffraction grating 36, and then, the direction of propagation of light inside optical module 1 depends on the wavelength of the light. Thus, as indicated in Fig. 8, light propagating along light paths of different (lateral) directions can be simultaneously present, e.g., when white light or another mixture of different wavelenghts enters optical module 1.

In a first interpretation, the embodiment of Fig. 8 is a fully passive optical module 1. Fig. 9 illustrates a vertical cross-section through the optical module of Fig. 8 in this first interpretation. The dotted line and the open arrow in Fig. 8 indicates where the cross- section is taken. On the right-hand side, there are four transparent portions t' (cf. Fig. 8) through which diffracted light can exit optical module 1. The color (or wavelength) of the light exiting the respective transparent portions t' will be different for the four

5 transparent portions t'. Prisms 38 are provided for redirecting the light.

Instead of letting the light exit through optics member O, one could also let the light exit through substrate member P (not shown in Figs. 7, 8). In this case, in or at optics member O, one or more at least partially reflecting elements such as optical mirrors could be provided reflecting diffracted light towards subtrate member S in which l o transparent portions t' would be present.

Of course, fully passive optical modules can also be provided in cases where light solely propagates substantially along one plane comprising the vertical axis (z). Fully passive optical modules, e.g., the before-described one, can be useful in or as optical

communication devices. Or they may constitute a microscope or a telescope or

15 binoculars or a portion of one of these. Or they could, upon light entering the module, let escape light of certain colors only or let escape light of certain colors in different places. But also an opto-electronic module may constitute an optical communication device or a portion thereof.

Fig. 10 is an illustration of a vertical cross-section through the optical module of Fig. 8 0 in a second interpretation. In this case, optical module 1 is an opto-electronic module.

Four light detecting elements 26 such as photo diodes are provided for detecting diffracted light of different wavelengths. Light enters optical module 1 through substrate member S.

In any interpretation, the embodiment of Fig. 8 may constitute a (simple) spectrometer. 5 In the first interpretation, detection can be done using a human eye, or diffracted light exiting optical module 1 can be further processed or analyzed by one or more additional devices. Note that in Figs. 9 and 10 and also in Figs. 12, 13 and 14 below, the members O, S and P are not clearly distinguished in the drawing. As has been mentioned before, it is possible to provide that optics member O and separation member S or substrate member P and separation member S are unitary parts. And it is of course also possible to provide that they are distinct parts, e.g., as drawn in other Figures, e.g., Figs. 1 to 6 and 15 (cf. below). It is, in general, possible to provide for any of

— a separate separation member S; or

— a separation member S comprised in optics member O; or

— a separation member S comprised in substrate member S; in any described embodiment.

Figs. 11 to 14 illustrate another example for the possibility to make use of more than one lateral direction in an optical module. Fig. 1 1 is an illustration of a lateral view of a corresponding optical module 1, Figs. 12 to 14 are illustrations of different vertical cross-sections through optical module 1 of Fig. 11. The locations where the cross- sections are taken, are indicated in Fig. 11 by the dotted lines and open arrows.

Light enters optical module 1 of Figs. 1 1 to 14 through transparent portion t and is then subsequently reflected by four passive optical components 30, more particularly by optical mirrors Ml, M2, M3, M4. An elaborate imaging and/or beam shaping may thus be achieved. Then, the light impinges on active optical component 20, more particularly on a light detector, e.g., on an image detector. This optical module 1 may thus constitute, e.g., a photographic device.

It is to be noted that separation member S is particularly shaped in this embodiment. A portion thereof can be considered a light shield which keeps unwanted light from impinging on active optical component 20. Thus, this portion has a function at least similar to that of spacer portions Sb, Sb',... in, e.g., Figs. 6 and 7. This portion can, as visible in Fig. 14, extend from a face Fl of optics member O to a face F2 of substrate member S. Fig. 15 is a cross-sectional view of a device 10 comprising an optical module 1. In many aspects, this optical module 1 is similar to the one of Fig. 1, cf. also the respective reference numerals. But the optical module 1 of Fig. 15 comprises two separate channels: one emission channel (on the right-hand side of Fig. 15) and one detection channel (on the left-hand side of Fig. 15). A spacer portion Sp of spacer member S optically separates the two channels; it can thus be referred to as a channel separator Sp. Thus there is no cross-talk between the channels (provided channel separator Sp is non- transparent). Separation member S comprises two separate openings 4 and 4', respectively, one for each channel. The emission channel comprises an emission member 22 as an active optical component 20, e.g., an LED. The detection channel comprises, as an active optical component 20, a number of detecting members 24, such as photo diodes, wherein a muti-pixel detector could be provided, too. The detection channel furthermore comprises passive optical components 30, more particularly a diffraction grating 36 and an optical mirror 32. And, in the detection channel, a spacer portion Sb functioning as a light shield is provided, similar to the spacer portions Sb in Figs. 5 and 6.

Light emitted by emission member 22 traverses transparent portion t comprising lens member L, usually for beam forming. If the light thus emitted from optical module 1 then interacts with an external object, a portion thereof can finally enter optical module 1 , more particularly the detection channel. That light is then diffracted by diffraction grating 36 and, at least in part, reflected by passive optical component 30 and, again at least in part, may impinge on one or more of the detecting members 24.

The amount of so-detected light and it distribution over the detecting members 24 may allow to draw conclusions with respect to color and/or position of external objects, wherein this position refers to a relative position of the external object with respect to optical module 1. Such an optical module 1 can be, e.g., a proximity sensor and/or a (simple) spectrometer (having its own light source). As is clear from the above, many kinds of optical arrangements can be realized within the framework of the invention, e.g., various arrangements which in general would be particularly suitable for realization using slab optics. But also standard optical setups can be realized in a miniaturized and mass-producible way, wherein passive as well as active optical modules can be provided.

By means of the invention, various optical arrangements can be realized in a miniscule optical package (module 1).

Claims

Patent Claims:

1. An optical module comprising

— a first member having a first face which is substantially planar, wherein

— a second member having a second face facing said first face, which is

substantially planar and is aligned substantially parallel to said first face; — a third member comprised in said first member or comprised in said second

member or distinct from these, which comprises an opening, in particular wherein said third member is a unitary part; and

— an optical element; wherein said first member comprises a transparent portion through which light can pass, wherein said optical element is attached to said first face or is comprised in said first member at said first face, and wherein said optical element is spaced apart from said transparent portion and located within said opening,

2. The module according to claim 1 , wherein outer bounds of a vertical silhouette of the module and outer bounds of a vertical silhouette of said first, second and third members each describe a substantially rectangular shape.

3. The module according to claim 1 or claim 2, comprising an at least partially reflective element, wherein said at least partially reflective element is attached to said second face or is comprised in said second member at said second face, in particular wherein said at least partially reflective element is an optical mirror.

4. The module according to claim 3, wherein said transparent portion, said at least partially reflective element and said optical element are mutually arranged in such a way that light passing through said transparent portion can propagate along a path interconnecting said transparent portion and said at least partially reflective element and interconnecting said at least partially reflective element and said optical element.

5. The module according to claim 4, wherein said path comprises at least two path portions running along different directions, said different directions differing in their respective lateral components.

6. The module according to one of the preceding claims, wherein at least one of said first and second members, in particular both, said first and second members, are, at least in part, made substantially of an at least substantially non-transparent material.

7. The module according to one of the preceding claims, wherein said third member is, at least in part, made substantially of an at least substantially non- transparent material.

8. The module according to one of the preceding claims, wherein said first, second and third members are of generally block- or plate-like shape, possibly comprising at least one hole.

9. The module according to one of the preceding claims, wherein at least one of said first and second members substantially is a printed circuit board or a printed circuit board assembly.

10. The module according to one of the preceding claims, wherein said third member is at least one of made of a hardened hardenable material and obtained using a replication process.

11. The module according to one of the preceding claims, wherein said optical element is at least one of made of a hardened hardenable material and obtained using a replication process.

12. The module according to one of the preceding claims, wherein said optical element is a passive optical component, in particular an at least partially reflective element, or an active optical component, in particular a light emitting element or a light detecting element.

13. The module according to one of the preceding claims, wherein said first member comprises a non-transparent blocking portion, in particular wherein said transparent portion is surrounded by said blocking portion.

14. The module according to one of the preceding claims, wherein said transparent portion is substantially made of a transparent material, in particular of a hardened hardenable material.

15. The module according to one of the preceding claims, wherein said transparent portion comprises a passive optical component, in particular an optical structure, more particularly one or more of a lens, a lens element, a prism, a transmission diffraction grating.

16. The module according to one of the preceding claims, comprising a second optical element attached to said second face or comprised in said second member at said second face, and wherein the earlier mentioned optical element is a second at least partially reflective element, and in particular wherein said second optical element is a passive optical component, in particular an at least partially reflective element, or an active optical component, in particular a light emitting element or a light detecting element.

17. The module according to one of the preceding claims, wherein the module forms a first and a second channel, said first channel comprising said optical element , said module comprising an active optical component, said active optical component being comprised in said second channel, in particular wherein said optical element is an additional active optical component.

18. The module according to one of the preceding claims, comprising an inside volume and a housing enclosing said inside volume, said housing being, except for said transparent portion, completely non-transparent, such that light can enter or exit said inside volume solely through said transparent portion, in particular wherein said first, second and third members contribute to said housing, more particularly wherein said first, second and third members form said housing.

19. An appliance comprising a multitude of optical modules according to one of the preceding claims.

20. A method for manufacturing a device, the method comprising the step of a) providing a first wafer comprising a multitude of transparent portions through which light can pass;

b) providing a multitude of optical elements;

wherein each of said multitude of optical elements is attached to said first wafer or is comprised in said first wafer, and wherein each of said multitude of optical elements is spaced apart from any of said multitude of transparent portions.

21. The method according to claim 20, comprising the step of k) manufacturing each optical element of said multitude of optical elements using a replication process, in particular using embossing.

22. The method according to claim 20 or claim 21 , comprising the step of m) manufacturing each transparent portion of said multitude of transparent portions using a replication process, in particular embossing.

The method according to one of claims 20 to 22, comprising the steps of providing a second wafer; providing a third wafer, wherein said third wafer is comprised in said first wafer or is comprised in said second wafer or is distinct from these, and wherein said third wafer comprises a multitude of openings; and e) forming a wafer stack by stacking said first, second and third wafers, such that said third wafer is arranged between said first and second wafers and that each of said multitude of optical elements is allocated with an opening of said multitude of openings.

24. The method according to claim 23, comprising at least one of the steps of n2) manufacturing said second wafer using a replication process, in particular

embossing.

25. The method according to claim 23 or claim 24, wherein said second wafer comprises a multitude of at least partially reflective elements.

26. The method according to one of claims 23 to 25, comprising the step of f) separating said wafer stack into said multitude of devices, in particular into a multitude of optical modules; more particularly wherein each of said devices comprises

— at least one of said multitude of transparent portions;

— at least one of said multitude of optical elements; and

— at least one of said multitude of openings.

27. A method for manufacturing a device, said device comprising an optical module, the method comprising manufacturing said optical module according to one of claims 20 to 26, in particular wherein said device comprises an optical module according to one of claims 1 to 19 and/or wherein said device comprises a printed circuit board on which said optical module is mounted.

28. A device comprising an optical module, wherein said optical module is an optical module according to one of claims 1 to 19, in particular wherein said device comprises a printed circuit board on which said optical module is mounted.