Photonic Devices for Vehicle Evolution - The Latest in Optical MEMS and Solid State Photonics HAMAMATSU PHOTONICS UK Nov 2015 Jack Bennett
Company Overview 4 Divisions Technology company, with focus on extensive research Founded 1953 Over 4000 Employees World leader in Photonics Largest Photonics company in the world today Complete one-stop-shop for all needed know-how, design and high reliability mass production Best known for - The LHC (CERN - Higgs Boson) But also - Well over 100 million devices built into cars 2
Products of Solid State Division Si photodiodes APD/ MPPC Photo ICs Image sensors PSD Infrared detectors Visible sensors Colour sensors LED Optical comms Flat panel sensors Mini-spectrometers Modules Automotive devices LCOS-SLM 3
Markets and Applications Industrial Automotive Consumer (Bio-) Medical and Dental High Energy Physics and Science Analytical 4
Automotive Applications 5 16-Oct-15
Setting the Scene for the Future What are the megatrends? Rise of Industry 4.0 and IoT (internet of things includes vehicles) Rise of Automation (vehicles + many other things) Connectivity (cars the next big platform?) Urbanisation Smart cities, smart infrastructure management (interact with cars) Trend to small size, high speed, green devices ( Photonics) Software, big data, cloud computing etc Hamamatsu sees future as evolving from a detector company To IC, ASIC, CMOS, MOEMS company More integration, more functionality Future markets will be driven by use cases, not always technology Many new applications being thought up, and new industries created with MEMS/MOEMS and Photonic devices 6
What is MEMS / MOEMS? MOEMS Micro Opto Electro Mechanical Systems Bringing together optics, electronics and mechanical moving parts in micro-scale components MEMS/MOEMS a focus and key technology for us 7
What is MEMS / MOEMS? MEMS Technology 8
MEMS Mirrors This is a MEMS Mirror : ~1 mm diameter mirror Capable of scanning in 2 dimensions, many thousands of times per second Then, if you focus a Red/Green/Blue laser onto this you effectivly have a full colour laser projector This requires no complex optics (because the laser beams are collimated), a very small volume and a small amount of power 9
What is MEMS / MOEMS and a Micro Mirror? 10
Structure and Operating Principle As you alternate the current in the wire, a force is produced on the mirror (Lorentz Force) The mirrors are actuated at their resonant frequency, or in static mode It uses innovative, fatigue-free actuation (no mechanical contact or gearing) 11
Example of [Gen-1] Demo Unit (Not Product) 12
Key Features Small size Low voltage operation <5V Low power consumption Wide oscillation angle High speed Sensitivity to dust None Sensitivity to radiation None Use in resonant mode (resonant frequency), or static mode (DC or steering mode) Magnetic actuators have high linearity, high mirror control & direct and precise mirror position sensing The laser beam used is collimated, then the image will always be in focus, so there is no need for complex optics Displays using lasers have high Illuminance and high colour reproductivity 13
Other Applications Creating structured light for 3D imaging/mapping and machine vision or factory automation Smart light pattern projection Gas sensing (the larger area 2mm devices) Replacing galvos and mechanical mirrors in scanners. Only not for high power applications yet. Beam switching (optical fibres, high speed comms, multi-gas sensing etc) Pico projectors Smart glasses and helmet / visor displays Retina scanning Vehicle Headlights 14 16-Oct-15
MEMS Mirrors We believe laser MEMS based HUDs will provide the image clarity, resolution, wide angle and compact size required for the future of automotive HUDs Laser technology is not yet proven in the automotive sector but interest is large due to the technology's potential Hamamatsu Photonics are one-stop company for all needed know-how; Our Solid State Division and Integral Optics Division design all core elements Mass production capability High quality & reliability consistent with the automotive sector The next generation of opto-semiconductors are being realised through MOEMS technology 15 16-Oct-15
MEMS Spectrometers - Background Every element and compound will absorb light at specific wavelengths, like a fingerprint This technique is called absorption spectroscopy Spectroscopy can be used for fuel quality measurements, AdBlue measurements, exhaust gas analysis, alcohol checking etc MOEMS technology shrinks these devices from printer/handheld sized, to fingertip sized Multi-gas spectral measurement 16 16-Oct-15
MEMS Spectrometers New Technology Micro-spectrometer MEMS-FPI MEMS-FTIR Diffraction type spectrometer UV Near-IR Sensitivity x 100 Hermetically sealed Fabry-Perot Interferometer Near-IR to Mid-IR Tuneable Filter Technology Low cost Fourier Transform Interferometer Near IR (Mid-IR in future) High speed World first 17 16-Oct-15
3D ToF Distance Image Sensors 3D Imaging Obstacle Detection Gesture Control 18
ToF Distance Image Sensors 19
3D Imaging - Background Gauging the distance, size and shape of an object is of paramount and selfevident practical importance in everyday life Nature has evolved a variety of ways for organisms to obtain 3-D information: stereoscopic vision utilizing two or more eyes, and sonar ranging are two examples Extending this ability to inanimate systems such as robots, decision makers in automated assembly lines, or self-driving vehicles has been and continues to be an active area of research and development The breakthrough is the development of a CMOS-architecture imaging array where each pixel is a photonic mixer device We will take a look at a type of 3-D camera, referred to as an indirect timeof-flight (I-TOF) camera 20
Principle of Operation 21
Example 22 16-Oct-15
Distance Accuracy An achievable uncertainty of a few cm, for a distance of a few meters, is low enough for I-TOF cameras to find many practical applications Distance uncertainty as a function of collected charge The more light there is the more accurate the distance resolution 23 16-Oct-15
Connectivity - Information Transfer We will need a high speed communication / data transfer system to handle the ever increasing amounts of data We are developing the next generation 5 Gb/s MOST transceivers 24 16-Oct-15
What is MOST? (Media Oriented Systems Transport) MOST is a fibre optic transceiver solution, for audio/video/other data transmission via the MOST bus The latest generation is capable of 150 Mbps (per channel) Used to transport data between infotainment devices, eg, radio to speakers, Blu-ray player to HD screen, GPS etc Also a MOST Ethernet channel available, so it is compatible with external devices like smartphones MOST is the standard in cars today Advantages such as the low weight of fibres, high quality of signals and no EM noise can interfere with optical signals 25 16-Oct-15
MOST Next Gen 5 Gb/s 50 um fibre, GaAs photodiode and VCSEL emitter will be used 26 16-Oct-15
Distance and Position Measurement / LIDAR Time of Flight (TOF) measurement 27
LIDAR Light Sources New Pulsed Laser Diodes 28
LIDAR Detectors APDs (avalanche photodiodes, gain ~100) APD array technology Custom hybrid devices - APDs with TIA / IC MPPC (multi pixel photon counters) - Silicon photomultipliers (gain ~ 1,000,000) Huge advancements in MPPC performance (Solid state version of a PMT) 29
LIDAR - MPPCs Key technology It is a multi-pixelated APD operated in Geiger mode MEMS fabrication processes (TSV technology) Silicon, Solid State, low cost Photomultiplier - gain ~1,000,000 Small size, high speed, rugged, low voltage operation compared to a PM-Tube The total output from incident photons varies in proportion with the number of pixels that are excited with a certain probability 30
What technology improvements have Hamamatsu made? Reduced crosstalk 31
What technology improvements have Hamamatsu made? Reduced crosstalk Reduced afterpulsing 32
What technology improvements have Hamamatsu made? Reduced crosstalk Reduced afterpulsing Reduced dark count rate 33
What technology improvements have Hamamatsu made? Reduced crosstalk Reduced afterpulsing Reduced dark count rate Increased fill factor Pixel Pitch Previous SiPM Latest SiPM 50um 61% 74% 34
What technology improvements have Hamamatsu made? Reduced crosstalk Reduced afterpulsing Reduced dark count rate Increased fill factor Increased PDE PDE = QE x Fill Factor x Avalanche Probability 35
What technology improvements have Hamamatsu made? Reduced crosstalk Reduced afterpulsing Reduced dark count rate Increased fill factor Increased PDE Increased operating voltage range 36
Headlight, LED and Display Control Automatic Headlight control. Control of LED or lamp brightness and colour for dashboard instruments and displays in the car. Photo ICs (Photodiode + IC) Photodiodes with RGB filter S9705 Light to frequency converter S11153-01MT Photo IC diode S11154-01CT Photo IC diode S9067-101 Photo IC diode S11012-01CR Digital Color Sensor S10917-35GT Color Sensor 37 16-Oct-15
Customisation of Photo ICs 38 16-Oct-15
Photonic Applications in Automotive Report Market report on Photonic Technologies for the automotive industry Goal To provide to Automotive companies to make them aware of Photonics Put together by EPIC and Tematys 39 16-Oct-15
Vision We use the technologies of light to help create a future world with balance among all forms of life We call this Life Photonics We believe that photonics technology can provide the means to overcome many of the challenges mankind faces 40
Thank you Stand I31 http://www.hamamatsu.com/jp/en/community/automotive/index.html 41