Technologies

3D Range Image Technology

The world’s most advanced 3D Range Image Technology which is not affected by sunlight or the lighting environment

Three-dimensionally, in real time: New technology to obtain three-dimensional distance information at high-speed 50FPS.
Various kinds of information within the range of the imaging space such as distance to a targeted object, its height, and position, can be obtained without being affected by sunlight, the lighting environment, or installation conditions.

Principle of 3D Range Image Technology

The time light projected to a targeted object strikes the object and returns is measured in real-time by every 20,000 pixels to obtain a distant image. This technology uses CMOS image sensors specially designed to obtain the high-speed light sources of near-infrared LED and distance image data. (TOF method: Time-of-Flight, the time the light takes to bounce back to the sensor)
This mechanism enables 3D measurement of a targeted object and information output simultaneously.
Distant image cameras measure distance using the phase difference method, one kind of TOF method, where the degree of the phase lag of the reflected light is measured by flashing light-projection pulse at high speed.
When the distance is 0m, the phase difference is 0°. The bigger the phase difference is, the farther the distance becomes.
The method or measuring the phase difference is to receive light, shifting the phase of the light projection pulse, accumulate and average the electrical charges of each phase and then compare the resulting changes.
For example, if the phase difference output is compared at distance 0°(Detector A) and 180°(Detector B),100%voltage is generated at Detector A, while no voltage is generated at Detector B.
The output changes as distance becomes farther. In phase difference φ, the voltage of the shaded part below being integrated, and the distance is calculated by estimating the phase difference based on the output difference,
Actually, because two phases alone cannot cover all the phase differences of 360°, the phase differences of 0°, 90 °, 180°and 270°in each frame are compared and distance precision is maintained.

Comparison with conventional image retrieval technology

  3D Range Image stereo-vision 2D image processing
Method Measure the time it takes for light to hit the object and return. 2D images are acquired with two or more cameras and parallax is measured. 2D images are acquired from the camera and image processing is performed.
Calculation load
(little)
×
(much)
(depending on contents of the processing)
Size (shape)
(Possible to miniaturize)

(Certain size required)

(Possible to miniaturize)
Distance resolution
(Distance resolution decreases with distance)
×
(Impossible to measure distance)
For outdoor use
(Susceptible to sunlight or shadow)

(Susceptible to sunlight or shadow)
For use in darkness
(Possible)
×
(Certain brightness necessary)
×
(Certain brightness necessary)
Necessary conditions for measurement Nothing in particular Background and the targeted object require contrast to be measured Background and the targeted object require contrast to be measured
Precise positioning is necessary

Capable of measuring multiple information in real-time from the imaging space.

  • Capable of determining the depth to the object, its height, width, and shape
  • Capable of estimating direction of movement and relative speed from the distance to a targeted object, as well as its height, shape, relative location.

By processing distance information.

  • Capable of isolating and extracting a targeted object by processing distance information, even when the color of an object and that of the background are similar or without contrast.
  • Capable of recognizing the specific shape of a targeted object or its gestures in a complex background.
  • Capable of setting a specific detection range in 3D in virtual areas in space

Capable of simultaneous and real-time output of imaging data, composed of XYZ distance information and luminance information obtained from self-emitting light.

New technology unaffected by environmental conditions

Capable of indoor or outdoor use, because it is not affected by sunlight or shadow unlike 2D image processing or stereo-television which measure distance with multiple cameras.

Comparison with existing imaging technology

  3D Range Image Laser Scan
Method: It measures the time of light striking and returning from a targeted object The distance is measured by revolving a laser with a plygon mirror and scanning the plane.
Distance resolution ◎(Excellent distance accuracy)
Outdoor use
Use in darkness ○(possible) ○(possible)
Scan rate ○(50FPS /screen in maximum) ○(20 ~60 FPS /plane)
Detection range: three dimensional, 20,000 pixels can be measured simultaneously. Only one plane one optical axis is scanned.

Detection in 3D space
Substantial expansion of range

In general, Optex technology can construct virtual 3D areas in imaging space, while general distance measurement obtains plane data by measuring one point or scanning a point horizontally.
The detectable range has expanded significantly as a result of this technology,