photonic devices for vehicle evolution - · pdf filephotonic devices for vehicle evolution...
TRANSCRIPT
Photonic Devices for Vehicle Evolution
- The Latest in Optical MEMS and Solid State Photonics
Jack Bennett
HAMAMATSU PHOTONICS UK – Nov 2015
2
Company Overview
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
But also - Well over 100 million devices built into cars
Best known for - The LHC (CERN - Higgs Boson)
4 Divisions
3
Products of Solid State Division
Si photodiodes APD/ MPPC Photo ICs Image sensors PSD
Infrared detectors Visible sensors Colour sensors LED Optical comms
LCOS-SLM Flat panel sensors Mini-spectrometers Modules Automotive devices
4
Markets and Applications
(Bio-) Medical and Dental Analytical
Industrial
High Energy Physics and
Science
Automotive Consumer
6
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
7
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
9
MEMS Mirrors
~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
This is a MEMS Mirror :
11
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)
13
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
14 16-Oct-15 14 16-Oct-15
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
15 16-Oct-15 15 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
16 16-Oct-15 16 16-Oct-15
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
MEMS Spectrometers - Background
MOEMS technology shrinks these devices from printer/handheld sized, to fingertip
sized – Multi-gas spectral measurement
17 16-Oct-15 17 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
20
3D Imaging - Background
Gauging the distance, size and shape of an object is of paramount and self-
evident 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 time-
of-flight (I-TOF) camera
23 16-Oct-15 23 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
24 16-Oct-15 24 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
25 16-Oct-15 25 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
26 16-Oct-15 26 16-Oct-15
MOST – Next Gen
5 Gb/s
50 um fibre, GaAs photodiode and VCSEL
emitter will be used
29
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)
30
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
33
What technology improvements have Hamamatsu made?
Reduced crosstalk
Reduced afterpulsing
Reduced dark count rate
34
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%
35
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
36
What technology improvements have Hamamatsu made?
Reduced crosstalk
Reduced afterpulsing
Reduced dark count rate
Increased fill factor
Increased PDE
Increased operating voltage range
37 16-Oct-15 37 16-Oct-15
Headlight, LED and Display Control
Automatic Headlight control.
Control of LED or lamp brightness and colour for dashboard instruments and displays in the car.
S9705 Light to
frequency converter
S9067-101
Photo IC diode S11153-01MT
Photo IC diode S11154-01CT
Photo IC diode
S11012-01CR
Digital Color Sensor S10917-35GT
Color Sensor
Photo ICs (Photodiode + IC) Photodiodes with RGB filter
39 16-Oct-15 39 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
40
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