Device and method for optically measuring distance with detector having photosensitive surfaces
A device for optically measuring distance, in particular a hand-held device, comprising an transmission unit ( 12 ) which is provided with a light source ( 17, 18 ) for emitting optical measuring radiation ( 13, 20, 22 ) towards a target object ( 15 ), and a capturing unit ( 14 ) which is arranged at a distance from the optical axis ( 38 ) of the transmission unit ( 12 ). The capturing unit ( 14 ) comprises at least one optical detector ( 54 ) for capturing optical radiation ( 16, 49, 50 ) reflected by the target object ( 15 ). The detector ( 54 ) of the capturing unit ( 14 ) comprises a plurality of light-sensitive surfaces ( 70, 72, 74; 170, 172, 174; 270, 272, 274; 370, 372; 470, 472; 570, 572 ) which are separated from each other and which are be activated separately. The invention also relates to a method for operating a device for optically measuring distance.
1. A hand-held device for optically measuring distance, with a transmission unit ( 12 ) that includes a light source ( 17 , 18 ) for emitting optical measurement radiation ( 13 , 20 , 22 ) in a wavelength range visible to a human eye towards a target object ( 15 ), and with a receiving unit ( 14 ) that is located a distance to an optical axis ( 38 ) of the transmission unit ( 12 ) and includes at least one optical detector ( 54 ) for receiving optical radiation ( 16 , 49 , 50 ) reflected by the target object ( 15 ),
wherein the detector ( 54 ) of the receiving unit ( 14 ) includes a plurality of photosensitive surfaces ( 70 , 72 , 74 ; 170 , 172 , 174 ; 270 , 272 , 274 ; 370 , 372 ; 470 , 472 ; 570 , 572 ), which are separated from each other and may be activated separately, and
wherein the photosensitive surfaces ( 170 , 172 , 174 ; 270 , 272 , 274 ; 370 , 372 ) of the detector ( 54 ) are formed and/or positioned such that an envelope ( 165 , 265 , 365 ) of these surfaces ( 170 , 172 , 174 ; 270 , 272 , 274 ; 370 , 372 ) tapers in the direction ( 61 ) of a beam displacement as the target object distances ( 48 ) decrease.
2. The device as recited in claim 1 , wherein means ( 55 ) are provided for switching individual photosensitive surfaces ( 70 , 72 , 74 ; 170 , 172 , 174 ; 270 , 272 , 274 ; 370 , 372 ; 470 , 472 ; 570 , 572 ) of the detector ( 54 ) on and off.
3. The device as recited in claim 1 , wherein the photosensitive surfaces ( 70 , 72 , 74 ; 170 , 172 , 174 ; 270 , 272 , 274 ; 370 , 372 ; 470 , 472 ; 570 , 572 ) of the detector ( 54 ) are formed and/or positioned such that an envelope ( 165 , 265 , 365 , 465 , 565 ) of these surfaces ( 70 , 72 , 74 ; 170 , 172 , 174 ; 270 , 272 , 274 ; 370 , 372 ; 470 , 472 ; 570 , 572 ) has a larger expansion in the direction ( 61 ) of a beam displacement for decreasing target object distances ( 48 ) than it does in the orthogonal direction.
4. The device as recited in claim 1 , wherein the envelope ( 165 , 265 , 365 , 465 , 565 ) of the photosensitive surfaces ( 70 , 72 , 74 ; 170 , 172 , 174 ; 270 , 272 , 274 ; 370 , 372 ; 470 , 472 ; 570 , 572 ) of the detector ( 54 ) has a symmetry axis located in the common plane ( 56 ) of the optical axes of the transmission unit ( 38 ) and the receiving unit ( 51 ).
5. The device as recited in claim 1 , wherein the expansion of the photosensitive surfaces ( 70 , 72 , 74 ; 170 , 172 , 174 ; 270 , 272 , 274 ; 370 , 372 ; 470 , 472 ; 570 , 572 ) of the detector ( 54 ) is at least so great that the measurement spot ( 58 ) of the returning radiation ( 16 , 49 ) from a target object ( 15 ) at a large object distance is detected in entirety.
6. The device as recited in claim 1 , wherein the expansion of the photosensitive surfaces ( 70 , 72 , 74 ; 170 , 172 , 174 ; 270 , 272 , 274 ; 370 , 372 ; 470 , 472 ; 570 , 572 ) of the detector ( 54 ) in the direction perpendicular to the optical axis ( 51 ) of the receiving unit ( 14 ) is at least so great that at least a portion of the measurement beam ( 50 ) returning from a target object ( 15 ) at close range still strikes the photosensitive surface ( 70 , 72 , 74 ; 170 , 172 , 174 ; 270 , 272 , 274 ; 370 , 372 ; 470 , 472 , 570 , 572 ).
7. The device as recited in claim 1 , wherein the light source ( 17 , 18 ) is a laser, in particular a laser diode ( 18 ).
8. A method for operating a device for optically measuring distance, as recited in claim 1 ,
wherein a detector ( 54 ) of a receiving unit ( 14 ) provided in the device includes a plurality (m) of separate, photosensitive surfaces ( 70 , 72 , 74 ; 170 , 172 , 174 ; 270 , 272 , 274 ; 370 , 372 ; 470 , 472 ; 570 , 572 ), of which only a portion (n, with n<m) of the available photosensitive surfaces ( 70 , 72 , 74 ; 170 , 172 , 174 ; 270 , 272 , 274 ; 370 , 372 ; 470 , 472 , 570 , 572 ) is activated when a distance measurement is performed.
9. The method for operating a device for optically measuring distance as recited in claim 8 ,
wherein only one photosensitive surface (n=1) ( 70 , 72 , 74 ; 170 , 172 , 174 ; 270 , 272 , 274 ; 370 , 372 ; 470 , 472 ; 570 , 572 ) of the detector ( 54 ) is active when a distance measurement is performed.
10. The method as recited in claim 9 , wherein when a distance measurement is performed, only that photosensitive surface ( 70 , 72 , 74 ; 170 , 172 , 174 ; 270 , 272 , 274 ; 370 , 372 ; 470 , 472 ; 570 , 572 ) of the detector ( 54 ) of the device is active that receives the largest portion of optical radiation ( 16 , 49 , 50 ) returning from a target object ( 15 ).
11. A method for operating a device for optical measuring device as recited in claim 1 , wherein a detector ( 54 ) of a receiving unit ( 14 ) provided in the device includes a plurality (m) of separate from one another photosensitive surfaces ( 70 , 72 , 74 ; 170 , 172 , 174 ; 270 , 272 , 274 ; 370 , 372 ; 470 , 472 ; 570 , 572 ), of which only a portion (m, with n<m) of the available photosensitive surfaces is activated when a distance measurement is performed.
12. A hand-held device for optically measuring distance, with a transmission unit ( 12 ) that includes a light source ( 17 , 18 ) for emitting optical measurement radiation ( 13 , 20 , 22 ) in a wavelength visible to a human eye towards a target object ( 15 ), and with a receiving unit ( 14 ) that is located a distance away to an optical axis ( 38 ) of the transmission unit ( 12 ) and includes at least one optical detector ( 54 ) for receiving optical radiation ( 16 , 49 , 50 ) reflected by the target object ( 15 ),
wherein the detector ( 54 ) of the receiving unit ( 14 ) includes a plurality of photosensitive surfaces ( 70 , 72 , 74 ; 170 , 172 , 174 ; 270 , 272 , 274 ; 370 , 372 ; 470 , 472 ; 570 , 572 ), which are separated from each other and may be activated separately, and
wherein the photosensitive surfaces ( 470 , 472 , 474 ; 570 , 572 ) of the detector ( 54 ) are formed and/or positioned such that an envelope ( 465 , 565 ) of these surfaces ( 470 , 472 , 474 ; 570 , 572 ) expand in the direction ( 61 ) of a beam displacement as the target object distances ( 48 ) decrease.