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to the low-cost, small-size, and long-ranging of the TFmini, the product itself has higher distance
measurement accuracy. It is more adaptable to different outdoor environments such as strong light,
different temperatures, and different reflectances. It has lower power consumption and more flexible
detection frequency. The product is compatible with both the UART and I
2
C interface. Different
interfaces can be switched by commands.
2.2 Principle of Distance Measurement
TFmini-S is based on ToF (Time of Flight). To be specific, the product emits modulation wave of near
infrared ray on a periodic basis, which will be reflected after contacting object. The product obtains
the time of flight by measuring round-trip phase difference and then calculates relative range between
the product and the detection object, as shown in Figure 1.
Figure 1 Schematics of ToF Principle
2.3 Main Characteristic Parameters
Table 1 Main Characteristic Parameters of TFmini-S
① Operating range based on a standard whiteboard with 90% reflectivity in indoor condition
② The distance measurement here is absolute accuracy, and the specific repeat accuracy will be described in section 2.4.
③ 2°is the theoretical value, from which the actual value will be different.
④ Only frame rates meeting the formula–1000/n (n is positive integer) can be set. The default frame rate is 100Hz.