Technical information
Toppan’s hybrid ToF™ Sensor
Our newly developed hybrid ToF™ (hToF™) sensor employs the unique ToF sensing method that combines the features of both indirect and direct ToF.
This sensor specializes in 3D sensing up to medium distances, which was difficult to achieve with the conventional indirect ToF method.
It is suitable for applications that require sensing in wide ranges, such as small robots, drones, and AGVs.
hybrid ToF™ Sensing Method
The Toppan’s unique hToF™ sensing method employs two features the indirect ToF (iToF) method and the direct ToF (dToF) methodNote1.
This method estimates ToF using multiple windows of short intervals (multi-time window technology).
Our new method is superior to the conventional iToF method for outdoor use because it is less susceptible to external light noise.
Subframe Operation
The subframe operation is available to change the position of the time window for each frame.
By combining multiple subframes, the measuring range can be extended.
This sensor can flexibly expend the working range by using this technique as well as the time window adjustment of each gate.
Dynamic Ambient Light Suppression Technology
The Dynamic Ambient Light Suppression (DALS) technology optimized for the hybrid ToF™ sensing method together with the multi-time window technique enables depth sensing with a wide working range even outdoors compared to conventional iToF sensors.
It is demonstrated that even in daylight (under 100k lux ambient light), our newly developed ToF sensor can measure objects (marker boards) located from a short distance of 1m to a medium distance of 20m.
Smart interference cancellation function
Smart interference cancellation function is a feature that automatically cancels the effects of interference caused by the ToF camera light source by dynamically controlling the sensor's internal operation.
By using this function, multiple drones and AGVs equipped with ToF cameras can be run simultaneously without mutual interference in the same working space. Since this function is embedded in the sensor, the user has no need to coordinate between ToF cameras.
High-sensitivity and high-resolution ToF pixels
Our newly developed ToF pixels are much smaller than our conventional products, and offer both high-definition and high-sensitivity performance.
A larger number of pixels will enable more precise area 3D sensing.
Related Information
Conference and Publication
2022 IEEE SYMPOSIUM ON VLSI TECHNOLOGY & CIRCUITS
C05-2: A Hybrid Indirect ToF Image Sensor for Long-Range 3D Depth Measurement under High Ambient Light Conditions
2023 IEEE Journal of Solid-State Circuits
A Hybrid ToF Image Sensor for Long-Range 3D Depth Measurement Under High Ambient Light Conditions