LIGHT SHIELD USING INTEGRATED LIGHTING TO CREATE OPACITY AND PRIVACY IN WINDOWS

Abstract

The invention provides a privacy window system (1) comprising a window panel (100), a lighting unit (200), and a control unit (300), wherein (i) the window panel (100) comprises a first surface (110), a second surface (120) and an edge (130), wherein the window panel (100) is transmissive for visible light wherein at least one of the surfaces (110,120) of the window panel (100) comprises surface structures (105), configured to generate visible privacy light (101) under irradiation with lighting unit radiation (201); (ii) instead of using edge-lighting for the irradiation of the window panel (100), the lighting unit (200) is configured to irradiate one of the surfaces (110,120) of the window panel (100) with said lighting unit radiation (201) thereby inducing said privacy light (101) and reducing visibility through the window panel (100) in at least one direction; and (iii) the control unit (300) is configured to control the lighting unit radiation (201) as function of an input signal.

Claims

1. A privacy window system comprising a window panel, a lighting unit, and a control unit, wherein: the window panel comprises a first surface, a second surface and an edge, wherein the window panel is transmissive for visible light, wherein at least one of the surfaces of the window panel comprises surface structures, wherein the at least one of the surfaces comprising said surface structures is configured to generate visible privacy light under irradiation with lighting unit radiation; the lighting unit is configured to irradiate at least one of the surfaces of the window panel with said lighting unit radiation from a first and/or from a second second side thereby inducing said privacy light and reducing visibility through the window panel in at least one direction; and the control unit is configured to control the lighting unit radiation as function of an input signal.

2. The privacy window system according to claim 1, further comprising a light sensor, wherein the control unit is further configured to control the lighting unit radiation as function of an ambient light sensor signal of the light sensor.

3. The privacy window system according to claim 2, comprising light sensors at both sides of the window panel, wherein the control unit is further configured to control the lighting unit radiation as function of ambient light sensor signals of both light sensors.

4. The privacy window system according to claim 1, further comprising a presence sensor, wherein the control unit is further configured to control the lighting unit radiation as function of a presence sensor signal of the presence sensor.

5. The privacy window system according to claim 1, wherein one or more of the color, color temperature, and the intensity of the lighting unit radiation is variable, wherein the privacy window system further comprises a user interface, wherein the control unit is further configured to control the lighting unit radiation as function of an input signal of the user interface.

6. The privacy window system according to claim 1, further comprising a second lighting unit arranged at another side of the window panel than the lighting unit, wherein the second lighting unit is configured to provide second lighting unit light, wherein one or more of the color, color temperature, and the intensity of the second lighting unit light is variable, and wherein the control unit is configured to control the lighting unit radiation as function of the second lighting unit light.

7. The privacy window system according to claim 1, wherein the window panel, the lighting unit, and the control unit are integrated in a single window unit.

8. The privacy window system according to claim 1, wherein the surface structures comprise reflective surface structures and wherein the lighting unit radiation comprises visible light.

9. The privacy window system according to claim 1, wherein the surface structures comprise luminescent material excitable by the lighting unit radiation.

10. The privacy window system according to claim 1, comprising a plurality of window panels, a plurality of lighting units, and said control unit, wherein the plurality of lighting units are configured to irradiate one of the surfaces of the plurality of window panels with lighting unit radiation, and wherein the control unit is configured to control the lighting unit radiation of the plurality of lighting units as function of the input signal.

11. The privacy window system according to claim 10, comprising a plurality of subsets (SS) of one or more window panels and one or more lighting units configured to irradiate said one or more window panels within the subset (SS), wherein said one or more lighting units of the plurality of subsets (SS) are independently controllable, and wherein each subset (SS) is functionally coupled to a user interface for controlling said one or more lighting units within the subset (SS).

12. Use of a privacy window system according to claim 1 for controlling privacy at at least one of the sides of the window panel.

13. Use according to claim 12, wherein the privacy window system is integrated in a hotel room.

14. Use according to claim 13, wherein the hotel room further comprises a second lighting unit configured to provide second lighting unit light, wherein one or more of the color, color temperature, and the intensity of the second lighting unit light is variable, and wherein the control unit is configured to control the lighting unit radiation as function of the second lighting unit light.

15. Use of a plurality of privacy window systems for controlling privacy at at least one of the sides of the plurality of window panels according to claim 12, wherein the plurality of window panels are integrated in a facade (BF) of a building (B), wherein the control unit is further configured to display one or more of a letter, a character, an icon, a symbol, a sign, a grapheme, and an illustration with the plurality of privacy window systems on the facade (BF).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Embodiments of the invention will now be described, by way of example only, with reference to the accompanying schematic drawings in which corresponding reference symbols indicate corresponding parts, and in which:

[0063] FIGS. 1a-1e schematically depict some aspects of the privacy window system; FIG. 1f shows an example of how the privacy window system may have effect;

[0064] FIGS. 2a-2d schematically depict some further aspects of the privacy window system.

[0065] The schematic drawings are not necessarily on scale.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0066] FIG. 1a schematically depicts an embodiment of a privacy window system 1 comprising a window panel 100, a control unit 300, and a lighting unit 200 comprising at least one light source (not shown) for generation of lighting unit radiation (201) during operation.

[0067] The window panel 100 comprises a first surface 110, a second surface 120 and an edge 130. The invention is especially not based on the use of edge lighting. Especially, there is no edge lighting at all. The window panel defines also two sides, a first side 1110, which is in herein only for the sake of understanding associated with the first surface 110, i.e. the first side 1110 is that space in direction I starting from the first side 1110, and a second side 1120 (opposite of the first side, relative to the window panel 100), which is in herein only for the sake of understanding associated with the second surface 120, i.e. the second side 1120 is that space in direction II starting from the second side 1120.

[0068] The window panel 100 comprises a transmissive material 102, such as glass or PMMA or another transparent polymeric material; even quartz may be possible. The window panel is transmissive for visible radiation. Hence, visible light may be transmitted through the window panel 100 in at least one of the directions.

[0069] At least one of the surfaces 110,120, here first surface 110 of the window panel 100 comprises surface structures 105, such as indentations or luminescent material structures (see also below). The at least one of the surfaces 110,120 comprising said surface structures 105, i.e. here the first surface 110, is configured to generate visible privacy light 101 under irradiation with lighting unit radiation 201. This radiation 101 is induced due to e.g. reflection, like Lambertian reflection of the lighting unit radiation (see below) as the the lighting unit 200 is configured to irradiate one of the surfaces 110,120 of the window panel 100 with said lighting unit radiation 201 thereby inducing said privacy light 101 and reducing visibility through the window panel 100 in at least one direction, here at least in the second direction II. The lighting unit radiation 201 is in this schematic embodiment provided to the first surface under a grazing angle. The angle between the (first) surface and the lighting unit radiation is indicated with angle .

[0070] Further, the control unit 300 may especially be configured to control the (one or more variables of the) lighting unit radiation 201 as function of an input signal, such as from a timer, a light sensor 401, such as in inside light sensor 415 or an outside light sensor 405 (or daylight sensor), or from a user interface 310, or from one or more of these. At the second side 1120, a further lighting unit 220 may be present. As the lighting unit light thereof, indicated with reference 221 may have influence on the transmissivity of the window panel (reflection at the first side 1110 may be less when the light level at the other side 1120 is higher), the control unit may control the lighting unit radiation 201 as function of the second lighting unit light 221. Further, the system 1 may e.g. include a presence sensor 410. The sensors are especially functionally coupled to the control unit 300.

[0071] If desired, the radiation 201 may be switched on, or its intensity may be increased, to temporarily generate visible privacy light (at an increased level) to impose or increase opacity in the second direction, thereby providing or improving privacy at second side 1120.

[0072] The lighting unit 200 is configured at the first side 1110, or at least irradiates the first surface 110 (comprising surface structures 105) from the first side 1110.

[0073] FIG. 1a is a very schematic drawing, which is not limiting. Here, a variant is shown wherein a window unit 2 is provided, wherein two or more of the window panel 100, a lighting unit 200, and a control unit 300, but at least the window panel 100, is integrated in a single unit (i.e. the window unit 2).

[0074] Reference 310 indicates a user interface, to instruct the control unit 300.

[0075] FIG. 1b schematically shows an embodiment wherein both surfaces 110 and 120 comprise the surface structures, with at each side a lighting unit 200, indicated with references 200a and 200b, respectively. In such embodiment, the privacy in both directions may be controlled (optionally independently). Hence, privacy at both sides 1110,1120 may be controlled. Alternatively the lighting units 200a, 200b are integrated into one lighting unit 200 comprising, for example, two independently controllable (arrays of) light sources (not shown).

[0076] The lighting unit 200a is configured at the first side 1110, or at least irradiates the first surface 110 (comprising surface structures 105) from the first side 1110; the lighting unit 200b is configured at the second side 1120, or at least irradiates the second surface 120 (also comprising surface structures 105) from the second side 1120.

[0077] FIG. 1c schematically shows a front view of the first side 110 with surface structures 105 of the window panel 100. The surface structures 105 may be arranged in a pattern. This pattern may be regular or irregular, or a combination thereof Dependent upon the radiation distribution (not shown) an asymmetric distribution of the surface structures may be desired, in order to provide a substantial homogeneous privacy light 101 (not depicted).

[0078] FIG. 1d schematically depicts in more detail embodiments of the surface structures 105. The top and middle surface structures may be reflective structures. These may be configured to provide a Lambertian distribution of the privacy light 101. Alternatively or additionally, luminescent material may be comprised by the surface structures 105, as schematically shown in the lower surface structure 105. The luminescent material is indicated with reference 106. Note that the surface structures 105 may also be configured to direct (privacy) light partly in the window panel 100 (not depicted).

[0079] FIG. 1e schematically depicts some variants how the first side may be irradiated with lighting unit radiation 201. Three variants of positions are indicated, with lighting units 200a, 200b and 200c, and their respective radiations 201a, 201b and 201c. Note that only one of these options may be chosen, or combinations of two or more of these. However, other configurations may also be possible. Lighting unit 200c in this schematic drawing may irradiate the first surface not with a grazing angle. However, in other configurations also more remote lighting units may irradiate the surface with surface structures with a grazing angle.

[0080] FIG. 1f shows a window panel 100 with on the left the lighting unit switched off, or with low intensity, leaving the window panel being transparent (in both directions), and with on the right side the lighting unit switched on or with high intensity. The privacy light substantially reduces the (apparent) transmission; the window panel appears opaque (status in right figure). The features at the other side of the window panel are hardly visible anymore (with this type and density of surface structures and this intensity of lighting unit irradiation). In both statuses, with either lighting unit radiation switched off or switched on, the person at the other side is able to look through the window panel.

[0081] FIG. 2a very schematically shows a building B with three floors, such as a hotel with three floors. The first floor includes two window panels 100, with each lighting units 200 serving the respective window panels. The respective lighting units are indicated with references 200-1 and 200-2. In this way, two subsets SS1 and SS2 are provided, that may be controlled by a singe control unit 300 and a single user interface 310. The second floor shows two rooms, the right room having two window panels, and a single lighting unit 200 (indicated with reference 200-3), a control unit 300 and a user interface 310; the right room having a single window panel 100 and a single lighting unit 200 (indicated with reference 200-4), and also a control unit 300 and a user interface 310. Hereby, two further subset SS3 and SS4, respectively, are provided. The top level shows by way of example a penthouse with two individually controllable window panels 100 with associated lighting units 200, indicated with reference 200-5 and 200-6, respectively. This provides two further subsets SS5 and SS6, respectively, which may be controlled with a single control unit 300 and user interface 310. Reference D indicates a door.

[0082] The control unit 300 at the lowest level or main floor may for instance include a master control unit 300. This is schematically depicted in FIG. 2b. The control unit 300 is the master control unit. Further, each room may include a user interface, indicated with reference 310a, 310b, 310c and 310d, respectively. The user interface 310 at the main floor may be used for master instructions, whereas the other user interfaces may be used for slave instructions. Optionally, each room may include its own control unit, either independent of each other, or subordinate to a master control unit (analogous to FIG. 2b).

[0083] FIG. 2c schematically depicts communications between the control unit 300 and several possible other elements, such as especially one or more lighting units 200, as well as one or more of a sensor 400, a timer system TS, and a user interface 310.

[0084] The system, as described herein, may include a plurality of such elements. The elements described herein other than the control unit 300, such as one or more of the lighting unit, the sensor, the timer system, the user interface, etc. may be functionally coupled to the control unit 300.

[0085] FIG. 2d very schematically depicts a room 500, especially a hotel room 510 having a wall 4 comprising a window panel 100 which is part of a privacy window system 1. Visibility in direction II may be limited by switching on the radiation of the lighting system (not shown). Hence, a light shield may be used to guarantee privacy of a person within the room, i.e. at side 1120 of the window panel 100. One may e.g. use the window panels of the facade BF to provide a color pattern, optionally changing in time. Especially when more window panels than schematically depicted are available, letters, words, pictures, etc. may be shown with the window panels as pixels. Hence, the control unit 300 may further be configured to display one or more of a letter, a character, an icon, a symbol, a sign, a grapheme, and an illustration with the plurality of privacy window systems 1 on the facade BF.