Wafer-level optical device having light guide properties

Abstract

An optical device (1) includes two prism bodies (41, 42) and four side panels (71-74) attached to both prism bodies (41, 42). A cavity (9) is thereby enclosed. A first reflector (81) can be present at a first side face (81) of the first prism body (41), and a second reflector (82) can be present at a second side face (82) of the second prism body (42). At least one of the prism bodies (41, 42) and/or at least one of the side panels (71-74) can be at least in part made of a non-transparent dielectric material such as a printed circuit board. In some implementations, an optoelectronic component (90) can be attached to the respective constituent of the optical device (1).

Claims

1. An optical device having a main direction, the optical device comprising a first, a second, a third and a fourth side panel, the first and third side panels being mutually parallel, and the second and fourth side panels being mutually parallel, and the main direction being aligned parallel to the first, to the second, to the third and to the fourth side panels, and the first and third side panels being at a right angle with respect to the second and fourth side panels; a first prism body comprising two base faces aligned parallel to the first and third side panels, one attached to the first side panel, the other attached to the third side panel; a second prism body comprising two further base faces aligned parallel to the first and third side panels, one attached to the first side panel, the other attached to the third side panel; a cavity enclosed between the first, second, third and fourth side panels and the first and second prism bodies; the first prism body comprising a first side face adjoining the cavity; the second prism body comprising a second side face adjoining the cavity; a first reflector present at the first side face which is shaped and aligned for redirecting light propagating in the cavity along a first direction to propagate along the main direction or vice versa; a second reflector present at the second side face which is shaped and aligned for redirecting light propagating in the cavity along the main direction to propagate along a second direction or vice versa; wherein at least one constituent of the optical device is at least in part made of a non-transparent dielectric material, wherein said at least one constituent is one of the first side panel, the second side panel, the third side panel, the fourth side panel, the first prism body, the second prism body.

2. The optical device according to claim 1, wherein the at least one constituent comprises at least one electrically conductive via for establishing an electrical connection through the non-transparent dielectric material across the at least one constituent.

3. The optical device according to claim 1, wherein the at least one constituent is at least in part constituted by a section of a printed circuit board.

4. The optical device according to claim 1, comprising an optoelectronic component.

5. The optical device according to claim 4, wherein the optoelectronic component is attached to the constituent.

6. The optical device according to claim 5, wherein the constituent comprises at least one electrically conductive contact pad, and wherein the optoelectronic component is attached to the contact pad.

7. The optical device according to claim 5, having an outer side and comprising at least one electrical contact at the outer side, wherein the optoelectronic component is electrically connected to the electrical contact.

8. The optical device according to claim 4, at least one of the side panels having two opposing primary sides, a respective first one of the primary sides facing the cavity, a respective second one of the primary sides facing away from the cavity, wherein the optoelectronic component is mounted at the second primary side.

9. The optical device according to claim 8, wherein the optoelectronic component is mounted on a substrate which is connected to the second primary side at which the optoelectronic component is mounted, via a spacer for defining a distance between the substrate and second primary side at which the optoelectronic component is mounted.

10. The optical device as in claim 4, in which the optoelectronic component comprises a light emitting component.

11. The optical device as in claim 4, in which the optoelectronic component comprises a light sensing component.

12. The optical device as in claim 4, in which the optoelectronic component comprises a microelectromechanical system.

13. The optical device according to claim 12, wherein the microelectromechanical system comprises a micromirror array.

14. The optical device as in claim 1, in which the first reflector comprises a reflective coating present on the first side face or wherein the first reflector comprises at least one mirror element attached to the first side face.

15. The optical device as in claim 14, in which the second reflector comprises a reflective coating present on the second side face or wherein the second reflector comprises at least one mirror element attached to the second side face.

16. The optical device according to claim 15, wherein the mirror element is an optoelectronic component.

17. The optical device according to claim 16, wherein the mirror element is a microelectromechanical system.

18. The optical device according to claim 16, wherein the microelectromechanical system comprises a micromirror array.

19. The optical device as in claim 1, in which the first side panel is transparent or comprises a transparent region, for letting pass through the first side panel light propagating along the first direction.

Description

(1) Below, the invention is described in more detail by means of examples and the included drawings. The figures show in a strongly schematized fashion:

(2) FIG. 1 a perspective illustration of an optical device;

(3) FIG. 2A a cross-sectional view of an optical device largely corresponding to the optical device of FIG. 1;

(4) FIG. 2B a side view of the optical device of FIG. 2;

(5) FIG. 3 a cross-sectional view of an optical device with side panels with transparent portions;

(6) FIG. 4 a cross-sectional view of an optical device with an optoelectronic component and a mirror element;

(7) FIG. 5 a cross-sectional view of an optical device with an optoelectronic component which is a MEMS;

(8) FIG. 6 a cross-sectional view of an optical device with an optoelectronic component mounted inside the cavity on a side panel;

(9) FIG. 7 a cross-sectional view of an optical device with an optoelectronic component mounted inside the cavity on a side face of a prism body;

(10) FIG. 8 a cross-sectional view of an optical device with an optoelectronic component mounted on a substrate in a side panel;

(11) FIG. 9 a cross-sectional view of an optical device with an optoelectronic component mounted on a substrate attached at a side panel via a spacer.

(12) The described embodiments are meant as examples or for clarifying the invention and shall not limit the invention.

(13) FIG. 1 is a perspective illustration of an optical device 1 with light guide properties which can be manufactured with high precision on wafer level.

(14) FIGS. 2A and 2B are a cross-sectional view and a side view, respectively, of an optical device 1 largely corresponding to the optical device 1 of FIG. 1. Basically, the dimensions of the constituents of the optical device 1 are different, and in FIG. 1, an optoelectronic component 90 illustrated in FIGS. 2A, 2B is not illustrated in FIG. 1.

(15) Optical device 1 includes two prism bodies 41, 42 and four side panels 61, 62, 63, 64 which enclose a cavity 9. These constituents 41, 42, 61, 62, 63, 64 are bonded to each other where they are adjacent to each other (cf. FIGS. 1, 2A, 2B), by means of a bonding agent such as a curable epoxy. This way, cavity 9 is hermetically closed such that contaminants cannot enter cavity 9.

(16) On side panel 62, a lens element 15 is provided, e.g., as illustrated, a concave refractive half-lens.

(17) Base faces 71, 72, 73, 74 of the prisms 41, 42 are of tetragon shape with two right angles and one acute and one obtuse angle. On mutually opposing side faces 81, 82 of prisms 41, 42, reflective coatings 81r and 82r, respectively, are provided, such that optical device 1 can function as a light guide (cf. the arrows in FIG. 2A): Light (a beam of light) can enter optical device 1 and cavity 9 through side panel 64 while propagating along an incidence direction), be reflected at reflective coating 81 to propagate along a main direction with respect to which the side panels are arranged in parallel, be reflected at reflective coating 82 to propagate along an exit direction and then to exit cavity 9 and optical device 1 through side panel 62 and lens element 15.

(18) Faces 81, 82 may be aligned parallel to each other and, e.g., may be aligned at 4510 with respect to the main direction.

(19) In cavity 9 at one of constituents 41, 42, 61, 62, 63, 64, an optoelectronic component 90 such a light sensing device, e.g., a photodiode, is provide. In FIGS. 2A, 2B, optoelectronic component 90 is mounted on side panel 61. Depending on the position of optoelectronic component 90, it may detect a fraction of light guided through optical device 1 or detect stray light. As an alternative, optoelectronic component 90 can be a light emitter such as an LED (cf. further examples below), e.g., for producing light superposing with light guided through optical device 1.

(20) At least one of constituents 41, 42, 61, 62, 63, 64 is at least in part made of a non-transparent dielectric material, such of a printed circuit board (PCB) base material, e.g., FR4/G10 or polyimide or another polymer-based material. More specifically, at least one of constituents 41, 42, 61, 62, 63, 64 includes a PCB (or a section of a PCB). This will usually apply at least those ones of the constituents 41, 42, 61, 62, 63, 64 at which an optoelectronic component 90 is attached. However, this may apply also other ones of the constituents 41, 42, 61, 62, 63, 64 (cf. further examples below). Transparent portions may be provided adjacent to and possibly surrounded by the non-transparent dielectric material so as to provide defined areas for light passing through the respective constituent (cf. further examples below). Such transparent portions may, e.g., be made of a transparent solid material such as a transparent polymer.

(21) Other ones of the constituents 41, 42, 61, 62, 63, 64 may be made of, e.g., a transparent material such as glass or a transparent polymer (cf. further examples below).

(22) With electrical conductors (vias) extending across the respective constituent present, optoelectronic components 90 can be electrically powered and/or controlled from outside optical device 1.

(23) FIGS. 3 to 9 are illustrations in a side view of various exemplary configurations of optical devices 1, mainly for highlighting some specific details each. Details or features present in the respective Figure which are not specifically related to those specifically discussed details may alternatively be embodied in a different manner, e.g., as described elsewhere in the present patent application such as in another one of the Figures.

(24) In the same manner as in FIGS. 2A, 2B, non-transparent material is illustrated by hatching, while transparent material is drawn in white. The meaning of reference symbols already explained before is sometimes not specifically repeated anymore.

(25) FIG. 3 illustrates an optical device 1 with transparent portions 62a and 64a in side panels 62 and 64, respectively. An amount of stray light entering or exiting optical device 1 can be reduced by the use of non-transparent material. But regions where light may enter or exit optical device 1 can be defined by the transparent portion.

(26) FIG. 4 illustrates an optical device 1 in which a mirror element 88 replaces a reflective coating on a side face (presently on side face 81). Such a mirror element 88 may be bonded to side face 81.

(27) Furthermore, FIG. 4 illustrates an optical device 1 with an optoelectronic component 90 present on side face 81. Optoelectronic component 90 may be a light sensing device or, as illustrated in FIG. 4, a light emitting device, e.g., an LED or a laser. Electrical connections across prism body 41 are symbolized at 95.

(28) FIG. 5 illustrates an optical device 1 with an optoelectronic component 90 which is a MEMS (microelectromechanical system) such as an array of actuable mirrors.

(29) FIG. 6 illustrates an optical device 1 with a light emitter as optoelectronic component 90 mounted inside cavity 9 on side panel 64. This is another way of letting light produced by optical device 1 propagate along a path similar to (in particular parallel to) the path of light guided through optical device 1.

(30) FIG. 6 also illustrates that at both large sides of a side panel (illustrated in FIG. 6: side panel 64), contact pads 99 may be present, for electrically contacting and mounting the optoelectronic component 90 and for providing electrical connections to optoelectronic component 90 from outside optical device 1, respectively.

(31) FIG. 7 illustrates an optical device 1 with an optoelectronic component 90 mounted inside the cavity on side face 82 of prism body 42. This can be understood as an example for the possibility to produce a superposition of diffuse light (produced by optical device 1) and directed light (guided through optical device 1).

(32) FIG. 7 also illustrates that more than one passive optical component may be included in optical device 1. E.g., one (15) may be present at a side panel (62) through which light exits optical device 1, and another one (15) may be present at a side panel (64) through which light enters optical device 1.

(33) FIG. 8 illustrates an optical device 1 with an optoelectronic component 90 mounted on a substrate 96 in a side panel (presently: side panel 64). This can provide improved possibilities for adjusting an optical path length for light propagating between optoelectronic component 90 and lens element 15.

(34) FIG. 9 illustrates an optical device 1 with an optoelectronic component 90 mounted on a substrate 95 attached at a side panel (64) via a spacer 98. This can provide improved possibilities for adjusting an optical path length for light propagating between optoelectronic component 90 and lens element 15.

(35) In such embodiments, transparent portion 64a may simply be an opening instead of being made of a solid transparent material such as a transparent polymer.