Kamerasysteme für die 3D-Erfassung
ams OSRAM bietet Bildsensoren, Mikrokameras, Flut- und Punktbeleuchtungsmodule für passive Stereovision, strukturiertes Licht und aktive Stereovision 3D-Sensorsysteme.
Passive vision systems
Passive vision systems capture multiple images of the scene from different positions. By matching recognizable features in the scene, distance can be calculated by triangulation methods.
- Mono camera systems comprise a single camera that must move relative to the scene to capture multiple views, while it’s position is tracked by an inertia sensor (IMU). For example, this technique is used for Augmented Reality applications that use the world facing camera in mobile phones.
- Passive stereovision systems offer improved robustness and resolution, by using two or more cameras that simultaneously capture different views of the scene. For example, this approach is widely for 3D scene and 6DoF position tracking in Virtual Reality headsets.
The maximum detectable depth range is proportional to the baseline (B) distance between cameras, and the image sensor resolution.
Whilst most passive camera systems use ambient visible light, IR flood illumination is also possible to address dark scenes.
Structured light and active stereovision
Passive vision systems have a limited resolution and robustness because the number of depth points is limited to the number of recognizable features. Some 3D scenes will not contain many features, leading to missed objects; for example a white object placed in front of a white wall.
Structured light systems effectively project an array of features. Our fully integrated VCSEL dot projector modules can project up to 15k high contrast dots, enabling high-resolution 3D data to be derived for even featureless scenes. The presence of the defined pattern also considerably reduces the computational load imposed by the software, as it offers many features to facilitate matching of the two images. Near infrared wavelengths are used, combined with a corresponding filter on the camera, to avoid interference from ambient light. For example, this approach is behind the user face recognition being implemented in smartphones.
At a minimum, a structured light system comprises a single camera and dot projector. Again, the maximum detectable depth range is proportional to the baseline (B) distance between them, and the image sensor resolution. This is, for example, the technology behind face recognition in smart phones.
Active stereovision systems combine two cameras with a dot projector, to give enhanced accuracy and robustness.
A comprehensive portfolio of products for vision systems
ams OSRAM offers a comprehensive portfolio of products to enable all types of vision based 3D sensors
- MIRA global shutter image sensors and wafer level optics can be combined to create ultra-small, IR enhanced, low power camera modules with reasolutions from 0.16 – 2.2MP.
- OSLON BLACK & P1616 Infrared LEDs and VCSEL flood illuminator modules offer powerful and efficient IR flood illumination from highly compact packages.
- BELAGO and BELICE VCSEL dot projector modules offer a fully integrated solution for IR structured light illumination.
- AS1170 driver IC drives LED and VCSEL illuminators synchronously with the camera shutter, featuring advanced production and safety features