Device and method for detecting presence of an object

摘要

The present invention relates to a method (60) and device (2, 40, 50) for detecting presence of an object (52) by means of influencing propagation of light (16) arriving to a detector (14). The device (2, 40, 50) for detecting presence of the object (52) at the device (2, 40, 50) comprises a light source (4), a first redirecting structure (6), a second redirecting structure (10), and a light detector device (14). The light source (4) is adapted to emit light (16) towards the first redirecting structure (6), which is adapted to redirect light (16) from the light source (4) towards the second redirecting structure (10), which is adapted to return light (16) from the first redirecting structure (6) back towards the first redirecting structure (6), which is adapted to redirect light (16) from the second redirecting structure (10) towards the light detector device (14). The device (2, 40, 50) has a sensing zone (18) formed by light (16) propagating between the first redirecting structure (6) and the second redirecting structure (10).

主权项

1. A device for detecting presence of an object at the device, the device comprising
a light source, a first redirecting structure comprising a first primary redirecting structure, a second redirecting structure comprising a second primary redirecting structure, and a light detector device, wherein the light source is adapted to emit light towards the first primary redirecting structure, the first primary redirecting structure is adapted to redirect light from the light source towards the second primary redirecting structure, the second primary redirecting structure is adapted to return light from the first primary redirecting structure back towards the first primary redirecting structure, and the first primary redirecting structure is adapted to redirect light from the second primary redirecting structure towards the light detector device, and wherein the device has a sensing zone comprising a first sensing zone formed by light propagating between the first primary redirecting structure and the second primary redirecting structure; and a planar waveguide comprising a first surface and a second surface and adapted for guiding light propagating from the light source towards the first redirecting structure, and for guiding light propagating from the first redirecting structure towards the light detector device, the planar waveguide further comprising a concave surface for receiving light from the light source and directing the received light towards the first redirecting structure.