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A handheld dental camera performs three-dimensional, optical measurements. The camera includes a light source that emits an illuminating beam, a scanning unit, a color sensor, and a deflector. The scanning unit focuses the illuminating beam onto a surface of an object to be measured. The surface of

A handheld dental camera performs three-dimensional, optical measurements. The camera includes a light source that emits an illuminating beam, a scanning unit, a color sensor, and a deflector. The scanning unit focuses the illuminating beam onto a surface of an object to be measured. The surface of the object reflects the illuminating beam and forms a monitoring beam, which is detected by the color sensor. Focal points of wavelengths of the illuminating beam form chromatic depth measurement ranges. The scanning unit stepwise displaces the chromatic depth measurement ranges by a step width smaller than or equal to a length of each chromatic depth measurement range, so that a first chromatic depth measurement range in a first end position of the scanning unit and a second chromatic depth measurement range in a second end position are precisely adjoined in a direction of a measurement depth, or are partially overlapped.

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1. A handheld dental camera that performs three-dimensional (3D), optical measurements, the camera comprising: a polychromatic light source that emits an illuminating beam;a scanning unit that includes a chromatic objective that focuses the illuminating beam, in terms of at least one wavelength of t

1. A handheld dental camera that performs three-dimensional (3D), optical measurements, the camera comprising: a polychromatic light source that emits an illuminating beam;a scanning unit that includes a chromatic objective that focuses the illuminating beam, in terms of at least one wavelength of the illuminating beam, onto a surface of an object to be measured,wherein a plurality of focal points of a plurality of wavelengths of the illuminating beam form a plurality of chromatic depth measurement ranges,wherein the illuminating beam is reflected by the surface of the object to be measured and forms a monitoring beam,wherein the scanning unit moves along a longitudinal axis of the camera between exactly two positions defined by end stops, from a first end position directly to a second end position, andwherein the scanning unit stepwise displaces the plurality of chromatic depth measurement ranges by a step width that is smaller than or equal to a length of each of the chromatic depth measurement ranges, such that a first chromatic depth measurement range in the first end position of the scanning unit and a second chromatic depth measurement range in the second end position are precisely adjoined in a direction of a measurement depth, or are partially overlapped;a color sensor that detects the monitoring beam; anda deflector disposed between the chromatic objective and the object to be measured, the deflector not being a part of the scanning unit, and the deflector deflecting the illuminating beam in a direction perpendicular to the longitudinal axis of the camera toward the object to be measured. 2. The handheld dental camera as defined in claim 1, wherein the polychromatic light source comprises a halogen lamp or a xenon gas discharge lamp having a radiation spectrum of from 300 nm to 2000 nm. 3. The handheld dental camera as defined in claim 1, wherein the polychromatic light source comprises a superluminescent diode (SLD). 4. The handheld dental camera as defined in claim 3, wherein the superluminescent diode (SLD) has a radiation spectrum of from 900 nm to 1000 nm. 5. The handheld dental camera as defined in claim 3, wherein the superluminescent diode (SLD) has a radiation spectrum of from 1500 nm to 1650 nm. 6. The handheld dental camera as defined in claim 1, wherein the polychromatic light source comprises a white light light-emitting diode (LED). 7. The handheld dental camera as defined in claim 1, wherein each of the chromatic depth measurement ranges has a length of from 0.5 mm to 5 mm. 8. The handheld dental camera as defined in claim 1, further comprising: a data processing unit or a connector that connects to the data processing unit,wherein, for each of the chromatic depth measurement ranges, the data processing unit causes a data set to be acquired and saved, andwherein the data processing unit forms an overall 3D data set covering a total depth measurement range by combining each data set for each of the chromatic depth measurement ranges. 9. The handheld dental camera as defined in claim 1, wherein the scanning unit is mechanically moved at a frequency of from 1 Hz to 1000 Hz. 10. The handheld dental camera as defined in claim 1, further comprising: a mirror disposed between the polychromatic light source and the surface of the object to be measured,wherein the mirror is pivotal about at least an axis perpendicular to the longitudinal axis of the camera such that the illuminating beam is moved stepwise in a direction perpendicular to the longitudinal axis of the camera by stepwise tilting of the mirror. 11. A method for performing three-dimensional (3D), optical measurements using a camera, the method comprising: emitting an illuminating beam from a polychromatic light source;focusing the illuminating beam, in terms of at least one wavelength of the illuminating beam, onto a surface of an object to be measured, using a chromatic objective of a scanning unit,wherein a plurality of focal points of a plurality of wavelengths of the illuminating beam form a plurality of chromatic depth measurement ranges, andwherein the illuminating beam is reflected by the surface of the object to be measured and forms a monitoring beam;detecting the monitoring beam using a color sensor; andmoving the scanning unit to exactly two positions defined by end stops, from a first end position directly to a second end position,wherein the chromatic depth measurement ranges are displaced stepwise by a step width that is smaller than or equal to a length of each the chromatic depth measurement ranges by the moving of the scanning unit, such that a first chromatic depth measurement range in the first end position of the scanning unit and a second chromatic depth measurement range in the second end position of the scanning unit are precisely adjoined in a direction of a measurement depth, or are partially overlapped; anddeflecting the illuminating beam in a direction perpendicular to a longitudinal axis of the camera toward the object to be measured. 12. The method as defined in claim 11, wherein the polychromatic light source has a spectral range of from 300 nm to 2000 nm. 13. The method as defined in claim 11, wherein the polychromatic light source has a spectral range of from 900 nm to 1000 nm or from 1500 nm to 1650 nm. 14. The method as defined in claim 11, wherein the plurality of focal points of the plurality of wavelengths of the illuminating beam are fanned out such that a length of each of the chromatic depth measurement ranges is from 0.5 mm to 5 mm. 15. The method as defined in claim 11, further comprising: acquiring and saving within the camera a data set for each of the chromatic depth measurement ranges;combining each data set and forming a 3D data set of the object to be measured, or transferring each data set to a data processing unit. 16. The method as defined in claim 11, wherein the scanning unit is moved at a frequency of from 1 Hz to 1000 Hz. 17. The method as defined in claim 11, further comprising: step-wise tilting a pivotal mirror such that the illuminating beam is moved stepwise in a direction perpendicular to the longitudinal axis of the camera. 18. The method as defined in claim 11, wherein the moving of the scanning unit includes measuring each of the chromatic measurement ranges and providing an overall measurement range, in a plurality of steps,wherein the method further comprises moving the scanning unit back to an initial position in a single step after, the moving of the scanning unit, andwherein a measuring cycle of the scanning unit is repeated until a measurement is complete. 19. The method as defined in claim 11, wherein the moving of the scanning unit includes measuring each of the chromatic measurement ranges and providing an overall measurement range, in a plurality of steps,wherein the method further comprises moving the scanning unit back to an initial position in a plurality of steps, after the moving of the scanning unit, andwherein a measuring cycle of the scanning unit is repeated until a measurement is complete.