The phase difference is determined by measuring four phases.

- Light modulated at a specific frequency is shone onto the surface, and the phase shift of the reflected light that returns is measured. (Δφ) We will find the distance from.
To find Δφ, 0° ・ 90° ・ 180° ・ 270° of 4 The signal is acquired in two phases.
Therefore, the depth frame 1 To get one lowest 4 number of exposures It is required.

Convert the phase difference to distance.

"Distance ambiguity" due to phase periodicity

Because the phase repeats periodically, if the distance to the target exceeds one cycle, it becomes impossible to distinguish which cycle the measured phase belongs to.
Example: At 60MHz, one period is 2.5m, so an object with a 3m period will be incorrectly measured as 0.5m.
Therefore, the maximum distance that can be measured is, in principle, one period of the modulation frequency (phase 0 to 2π).
The distance of one period is determined by the following formula, and it becomes shorter as the frequency increases.

For example, 1.5m for 100MHz and 2.5m for 60MHz.

iToF inherently possesses great potential in terms of high resolution, real-time capabilities, and low computational requirements.
However, its susceptibility to ambient light and short range have limited its practical applications.
​Hyperlux ID was developed to overcome this obstacle.

Problem ①: "The resolution is insufficient, making it impossible to capture fine details and small parts."

Many iToF sensors on the market are limited to VGA resolution. The Hyperlux ID boasts a high resolution of 1.2 megapixels, up to approximately four times the resolution of typical iToF sensors, enabling more precise measurements. Furthermore, because it supports binning, it can also be used as a more sensitive VGA sensor in applications where VGA resolution is sufficient.

Problem ②: "Depth calculation requires FPGAs and processors, making the camera large and expensive."

The AF0130 integrates depth calculation functionality into the sensor. This offers the following advantages:
-Reduced component costs: This allows for the elimination of high-performance FPGAs and other components used for calculations, leading to a smaller camera.
• Flexibility in processor selection: The computing resources of a high-performance processor can be allocated to other applications, or replaced with a lower-cost processor.
For customers who wish to use their own custom calculation algorithms, we also offer the AF0131, which does not have calculation capabilities.

Problem 3: "When measuring a moving object, the results tend to be inconsistent."

Conventional iToF sensors read data externally for each phase of exposure, which means there is a time lag between the first and last exposures. If the subject moves during this time, motion artifacts (blur) occur.

Hyperlux ID directly stores information for four phases in single-frequency mode and eight phases in dual-frequency mode in the memory within the pixel.
Because exposure for the next phase can be started in a very short time, the total exposure time for all four phases is reduced, minimizing blur. This is highly effective in dynamic environments such as measuring goods moving on a conveyor belt or measurements taken from moving robots.

Problem 4: "The measurable distance is short, and it cannot cover a large space."

Hyperlux ID features a dual-frequency mode that handles two modulation frequencies within a single frame.
External processing is unnecessary, the frame rate does not decrease, and exposure time is reduced by 8 phases thanks to in-pixel memory (the maximum resolution when using dual frequency is VGA).

In addition, the quantum efficiency (QE) in the 940nm band exceeds 40%, compared to 20-30​ ​% for conventional products. As reflected light weakens with distance, this improved sensitivity significantly contributes to increased measurement range and accuracy.

Problem 5: "It cannot be used outdoors due to the effects of sunlight."

iToF is generally susceptible to ambient light such as sunlight, and has tended to be limited to indoor applications. Hyperlux ID has enhanced ambient light rejection capabilities, allowing for accurate depth results even in sunlight.

Usage scenarios: This helps solve the following problems

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