WIDE-ANGLE RANGE IMAGING MODULE AND REALITY CAPTURE DEVICE COMPRISING A WIDE-ANGLE RANGE IMAGING MODULE
A range imaging module and a reality capture device comprising a range imaging module and configured to generate 3D measurement data for generating a digital representation of an environment. The range imaging module comprises a cover, which is transparent for at least part of distance measurement radiation of the range imaging module and which comprises a band-pass filter coating. The cover with the band-pass filter coating is arranged in a collimated beam region outside an imaging unit of the range imaging module and encloses the imaging unit, so that returning distance measurement radiation from an imaging field of view of the imaging unit first passes the cover with the band-pass filter coating and then the imaging unit.
1 . A range imaging module, which comprises:
an emitter unit configured to emit distance measurement radiation,
a range imaging receiver comprising a detection area with multiple photo sensitive detection elements for detecting returning parts of the distance measurement radiation,
wherein the range imaging receiver is configured to provide for each of the detection elements a distance measurement based on a time-of-flight measuring principle using the distance measurement radiation, and
an imaging unit configured to image substantially collimated returning distance measurement radiation from an imaging field of view, particularly an imaging field of view of 100°, onto the detection area, thereby separating a collimated beam region outside the imaging unit, where the returning distance measurement radiation is in a substantially collimated state, from a converging beam region after the imaging unit, where the returning distance measurement radiation is in a converging state,
a cover being transparent for at least part of the distance measurement radiation and comprising a band-pass filter coating, wherein the cover with the band-pass filter coating is arranged in the collimated beam region outside the imaging unit and encloses the imaging unit, so that returning distance measurement radiation from the imaging field of view of the imaging unit first passes the cover with the band-pass filter coating and then the imaging unit.
2 . The range imaging module according to claim 1 , wherein the band-pass filter coating is arranged on an inner surface of the cover.
3 . The range imaging module according to claim 1 , wherein the band-pass filter coating is arranged on an outer surface of the cover.
4 . The range imaging module according to claim 1 , wherein a shape of the cover is matched with the imaging unit in such a way that respective angles of incidence onto the band-pass filter coating are less than 0.5° for all chief rays of the returning distance measurement radiation within the imaging field of view of the imaging unit.
5 . The range imaging module according to claim 4 , wherein the band-pass filter coating is arranged on an inner surface of the cover and the imaging unit and the cover are configured in such a way that a sole impact of a refractive power of the cover lies in a defocusing effect on returning distance measurement radiation when it propagates through the imaging unit onto the detection area, wherein the defocusing effect can be compensated for the full imaging field of view of the imaging unit by refocusing a receiving lens of the imaging unit.
6 . The range imaging module according to claim 4 , wherein a shape of the cover is matched with the imaging unit in such a way that respective angles of incidence onto the band-pass filter coating are less than 0.2° for all chief rays of the returning distance measurement radiation within the imaging field of view of the imaging unit.
7 . The range imaging module according to claim 1 , wherein the imaging unit comprises a F-Theta lens or a fisheye lens and the cover has a spherical shape.
8 . The range imaging module according to claim 1 , wherein the cover is configured to be essentially free of refractive power compared to a refractive power of the imaging unit, particularly wherein an absolute value of the refractive power of the cover is 50 times, more particularly 200 times, less than an absolute value of the refractive power of the imaging unit.
9 . The range imaging module according to claim 1 , wherein the cover is made from glass substrate or an optical synthetic material, particularly Zeonex, polycarbonate or PMMA.
10 . A reality capture device configured to generate 3D measurement data for generating a digital representation of an environment, wherein the reality capture device comprises a range imaging module according to claim 1 and is configured to generate the 3D measurement data based on range images provided by the range imaging module.
11 . A reality capture device configured to generate 3D measurement data for generating a digital representation of an environment, wherein the reality capture device comprises a range imaging module according to claim 9 and is configured to generate the 3D measurement data based on range images provided by the range imaging module.
12 . The reality capture device according to claim 10 , wherein the reality capture device is configured to be carried and moved by a mobile carrier, particularly a person or a robot or a vehicle, and to be moved during a measuring process for generating the digital representation of the environment, wherein the measuring process comprises generation of mutually referenced 3D measurement data on the basis of range images provided by the range imaging module at different locations and poses of the reality capture device.
13 . The reality capture device according to claim 12 , wherein the reality capture device is configured to use localization data of a localization unit for providing referencing of the range images with respect to each other during the measuring process, wherein the localization data provide for determining pose information for a position and orientation of the reality capture device during the measuring process.
14 . The reality capture device according to claim 13 , wherein the localization data comprise inertial measurement data.
15 . The reality capture device according to claim 12 , wherein the reality capture device is configured for simultaneous localization and mapping (SLAM) to generate a three-dimensional map based on at least one of the range images provided by the range imaging module, inertial measurement data, and 2D imaging data.
16 . The reality capture device according to claim 10 , wherein the reality capture device comprises an event detector configured to classify the 3D measurement data for detecting an event within the environment.
17 . The reality capture device according to claim 10 , wherein the reality capture device comprises a further range imaging module, wherein the range imaging module and the further range imaging module are each configured to provide an imaging field of view of 90°, for generating respective range images.
18 . The reality capture device according to claim 10 , wherein the reality capture device comprises a further range imaging module, wherein the range imaging module and the further range imaging module are each configured to provide an imaging field of view of 180° for generating respective range images.