***Photonics West 2002
By John Latta
(1/22/02)
The optics industry is bifurcated by era and time: pre fiber
optics and post fiber optics. Unfortunately the post segment hit
the wall when the telecommunications stocks went bust along with
the capital spending. SPIE's Photonics West 2002 was a mixture of
the old and new. Photonics implies the integration of electronics
and optics and there was much of that on the floor. As we looked
over the exhibition is was the optical equivalent of Toy's R Us.
Many optics goodies. As reflective of the SPIE conferences this
was a big optics event. There were 2,600 technical papers, 100
short courses and 600 exhibitors in two halls.
This was also an international event with papers from many
countries and likewise with the exhibitors. Even the Russian
Academy of Sciences had a booth here, as did the Scottish Optical
industry. China and Japan are also well represented.
We picked up these top-level threads:
Two major markets have created significant opportunity and also
injected research activity into optics: optical fiber
communications and optical playback (CD and DVD).
The technologies of laser emission in semiconductors and
diffractive elements have spawned new optical components of which
fiber optics communications has been largely the beneficiary.
There is a micro optics revolution taking place but it is too
early estimate when and who this will impact industrial or end
user products. Although many of these products are for coherent
optics systems, i.e., they are diffractive, these are mostly
stand-alone components and not integrated at the wafer level.
In spite of huge investments, the integrated optical circuit is
not a reality but the show illustrates that significant advances
have been made.
A major stumbling block to integrated optics remains packaging of
the components into modules.
All of the players, who have had a focus on the
telecommunications market, are looking for other markets and
opportunities. A consistent thread from the floor is that the
bottom has fallen out of telecommunications.
Integrated Optics
One of the major challenges in the development of micro optics
lies between the polar ends of on-chip integration vs. module
integration. The latter then becomes a packaging issue and here
is where costs climb. In fact, the statement was made more than
once: The package is more costly than the components. Achieving
on-chip integration has been a holy grail in optics for decades.
What optics would like is the same economics of scale that
digital has gained in CMOS with silicon process technologies.
Liking it and achieving it is still the North and South Pole.
Avalon Photonics
We asked about on-chip extensions to VCSELs the answer was YES.
The execution is a little difficult. The fundamental problem is
that VCSELs are based on III V compounds. Thus, the low cost 850
nm VCSELs use a GaAs substrate. This limits the level of on chip
integration in addition to being a costly process technology.
Avalon Photonics is working to extend its VCSELs with on chip
lenses and photo detectors. One of the major advantages of both
is alignment, which is especially important in fiber systems. The
on-chip photo detector makes sense in the telecommunications
applications because the speed performance of the emitter and
detector can be matched. However, for many non-communications
applications a photo detector with GaAs technology is just not
required.
Silicon Light Machines
This company, now owned by Cypress Semiconductor, has a Grating
Light Valve (GLV) that is a MEMS structure done on silicon. The
GLV is diffraction grating in MEMS where in the on-state the GLV
acts like mirrors and in the off-state it likes a grating. The
advantages claimed include:
Fast operating speeds
Low insertion loss
Variable attention
Optical angular repeatability based on the silicon process
Scalability and
Fabrication with CMOS process.
GLVs have application in displays. A production part using GLV
was shown in the booth which is used for displays. Laser light
for GB hits three linear GLVs which act as modulators. An HDTV
display can be created which supports 1088 X 1920 with a refresh
rate of 250kHz.
Prospects for a Silicon Laser
There are huge advantages to a silicon laser for all the
integration opportunities. On the academic side both University
of Trento in Italy and University of Surrey in England are
reported to be close to showing lasers using silicon. Each
operates in region from 1.1 to 1.5 microns. The UK group has
actually shown light emission.
VCSEL - Is there life after 850nm?
VCSEL is a general-purpose laser light emitter? Wrong.
VCSELs have found broad applications in laser/coherent optics
systems? Wrong.
What is the story?
VCSEL (Vertical Cavity Surface Emitting Laser) use has focused on
the telecommunications market. It is an EO converter. Pump in
Gb/s and out comes modulated light. Line up with a fiber and it
is the beginning of a communications system. In discussion after
discussion it became clear that VCSEL technology has not risen
above this telecommunications use. Yet, with the collapse of the
telecommunications market virtually all the VCSEL players are
seeking other markets. It is more complex than just shifting
markets with the same products. Honeywell stated that it
introduced at 670nm laser to have a product in the visible red.
Yet, this did not meet the needs of the printer market and a 780
nm laser was developed. The reason cited was the characteristics
of paper required a different wavelength.
The potential of VCSEL is quite broad. Consider the VCSEL as just
another source of light. When put into an array the bandwidth of
the telecommunications goes up by the number of array members.
One company spoke of going to 1Tb/s with only an 8 X 8 array.
Yet, an array of VCSELs can also be used in displays, and there
are many issues to be addressed including tight packaging to
accomplish display density. VCSELs in spectrometers are another
application. Yet, an additional application is measurements and
this can include fluid flow, for example. Thus, the use of VCSELs
in high volume applications has not happened yet. As Honeywell
stated in its invited presentation - the era of hypergrowth is
over. We may log 30% growth this year not 200%. To continue to
grow the VCSEL market many changes will take place.
There have been laser edge emitters for some years and these have
not gained the traction expected of VCSELs. VCSELs have the
following advantages:
Use less power,
Have narrower line width,
Have uniform beam,
Take smaller die area,
More reliable and
Are relatively easy to package into the TO can.
All cited the expectation that VCSELs should be lower cost than
conventional edge emitters. The factors cite above, and
especially the power consumption, favor VCSELs in wireless
applications. VCSELs also face packaging issues due to a lack of
standardization and a limited number of wavelengths, mostly just
at 850 nm.
On the Show Floor - Focus on VCSELs
Honeywell
Honeywell gave a paper on its current manufacturing and fab. An
appeal was made in the talk to standardize on a package that is
not the TO-46. One of the reasons given is that this will not
scale to the high bandwidths. But more importantly the industry
will gain much by package standards. Honeywell proposed a new
package, which was shown. Honeywell is also focused on improving
the production efficiency. Number pictures were shown of their
fabrication facilities. These were of world class but did not
have the comprehensive look of a foundry fab. One objective they
have is the building of VCSEL products without the use of human
hands. An area where VCSELs have another advantage over edge
emitters is the ability to test them on the die before slicing.
Also being developed is the ability to do burn in again at the
wafer level. At the same time these objectives are accomplished
the hand processing of the die or individual components goes down
or is eliminated.
Honeywell also believes that there is the prospect for continuing
growth in telecom as the need for bandwidth extends to the home.
However, when asked if VCSELs have any place in PON, the obvious
answer was no. They responded, but we will serve the metropolitan
market. Implying, of course, that VCSELs will be present in
markets that demand active components.
ULM
The focus of ULM is to continue to drive the bandwidth with
arrays of VCSELs. They showed a 1/2Tb/s 8 X 8 array. The key to
this implementation was the use of flip chip. That is, all the
bonding and leads are out of the bottom of the chip with the
emissions from the bottom side facing up. I thought this novel in
that there is the potential to improve the VCSEL density, but
this was not addressed in the talk. Another advantage would be
die integration and in this design the VCSEL driver was also
integrated. Results were shown that even in a multimode VCSEL the
spectral width was only 2nm. The drive current for a TO-46 can
part is 7ma. In another example, a VCSEL with a 15mw of
continuous output had total power consumption, including driver,
of 960mw. The MTBF of an 8 X 8 array was predicted at 10**7
hours.
United Epitaxy Co.
This is a Taiwanese company moving into VCSELs. They make LEDs
and edge emitting lasers in the range of 650n, to 1550nm. They
are now making VCSELs and sought to show the audience with an
invited paper that UEP is a qualified supplier.
Avalon Photonics
Headquartered in Switzerland this company had made a strategic
decision to focus on just the data communications business.
However, 20% of the business is outside of this and as a result
of the turn down they now have a broader market focus. One market
cited is that of measurements but this is still too early to
emerge. From Avalon's perspective they have seen no displays
surfacing using VCSELs.
Laser Components
This is a distributor of components or small systems
applications. They had a section of the booth with edge emitters
and when I asked about VCSELs they directed me to the other part
of the booth. This was the instrument section and they have just
received exclusive NA distribution rights with a major VCSEL
company for the spectroscopy market. However, even this market
has yet to form and they are less certain of other markets. "All
of this is very new."
Fuji Xerox
Tucked away in a small table was Fuji Xerox with table pictures
of their VCSELs. When I asked where are the applications, the
response was much to my surprise. "It is telecommunications."
They originally got into VCSELs for laser printers, left this
application, moved to telecommunications and are now going back
looking at the use in printers. Development remains to be done
but it was not clear how much and when products might surface.
Photonic Products
Photonic Products, located in the UK, is a distributor of
conventional laser diodes. 60% of their business is distribution
and 40% is in creating and manufacturing small assemblies that
use laser diodes. When asked about VCSELs this was a turn off -
nothing. They are interested in the red VCSELs at 625nm but to
date no applications have emerged.
Optics Software
Optical analysis and design software has exploded in offerings
and capabilities. Optical analysis programs fit within 5
categories:
(1) Sequential Optical Analysis and Design
Traditional optics with lenses which relies on ray tracing from
an object point to an image point
(2) Non-Sequential Optical Analysis and Design
Illumination systems.
(3) Optics for Communications
A hierarchal stack of tools from semiconductor device design,
i.e., lasers, to communications link and network assessment
(4) Laser Optics
EM and physical optical analysis for lasers and coherent optics
(5) Optics Visualization
Seeing the impact of optics systems
The best way to address this is on a company-by-company basis.
Applied Optics Research
GLAD
Applied Optics Research has a laser and coherent optics program
that is widely seen as the best. This software fits within
category (4).
Photon Engineering
FRED
Incredible. We almost missed this. This fits into the Optical
Visualization category (5). Quite simply this is optical system
analysis by seeing. One can lay out a system and look at the
results in the form of rays or interference patterns. Everything
is in 3D and all the structures can be readily magnified, rotated
and manipulated. This is characterized as software for the small
organization that does not do optics design full time. Optics is
put into a visual environment. Its strength is non-sequential
optics (2) but FRED is really not a design program. The output of
FRED would then be used by the more conventional lens and
illuminator design programs. The program is in Beta and for this
it costs $2,500. The final version is due by July and is expected
to cost $2,900. Those that purchase now will receive 1 year of
support after the release and the final version.
Breault Research Organization
ASAP
ASAP is to non-sequential optics (2) what GLAD is to Laser Optics
(4). That is, when it comes to analyzing illumination systems
ASAP is the software tool. Its median user has a MS or PhD in
optics with many years of experience. However, in another booth a
user said - an effective ASAP user must be one that does this
nearly full time. It is a very sophisticated tool and to use it
effectively requires years of experience. The costs begin at $7k
and can reach up to $20k based on the modules purchased.
ORA
CODE V
CODE V is the most mature and complete lens design software
available. It is also the most expensive. Only a lease is
possible. The cost is $900/month per seat. CODE V has a
comprehensive interface that begins with a lens table, like an
Excel table. Such an interface is common with lens design
programs.
Multiple times in discussions on the show floor ORA came under
fire for their pricing. In fact, ORA was blunt in stating - the
lease model provides us with a continuing revenue stream. It also
provides a target for other lower cost programs that can be
purchased.
Light Tools
This is the non-sequential design program (2). The basic program
costs $400/month and for the illumination module it is another
$400/month.
For a complete software suite, CODE V and Light Tools, a company
could spend $20,400 per year per seat.
Focus Software
ZEMAX
Many times this software was referred to. Based on the demo I
received the user interface seemed as easy to use as CODE V but
possibly not as rich. What is significant is that this program
combines both sequential and non-sequential analysis. The pricing
is striking: SE $1,500; XE $2,500; and EE $3,500. A database of
500 lens designs is available for $300.
Lambda Research
OSLO
This is the other most talked about lens design program. There
are multiple versions that range in purchase price from $1,000 to
$5,000. Fits into category 1.
TracePro
The non-sequential design program which has three versions: all
reflectors $2,500; LC version for complex illuminator design
$5,000; and the expert version which will do analysis of LCD
panels $15,000. This is a category 2 program.
OPTIS
SPEOS
This program combines non-sequential optics with visualization.
After some booth discussion I can only describe this as a
marketing clueless European company - this is a French firm. They
cannot quote a price for the software unless they know the
application in detail. The best I could get was a price range
from $15 - 20k. There is a lens design program also but they ran
out of literature. The price begins at $2k. I have no idea why
they bothered to show up.
Engineering Synthesis Design
IntelliWave
IntelliWave is a unique program that is different from our set of
5 above. It does the analysis of Interferograms. One can image
the Interferograms and it will process from 1 to 12. There are
130 analysis functions.
From the Floor
Corning IntelliSense
Merged with Corning, IntelliSense is a nearly $1b investment in
the company by Corning. IntelliSense is a MEMS only company and
has 100 employees. They have fab and tools. The tool is the
industry-leading IntelliSuite software, which they label CAD for
MEMS. The software costs $30k on an annual basis and $72k for a
perpetual license. In optics, IntelliSense describes devices that
include: Micromirrors, Silicon Benches and Waveguided structures.
The applications include optical self-assembly, scanners and beam
steering. Another interesting application of MEMS is in RF
components. RF MEMS devices include: capacitors, high-q
inductors, tunable capacitors and switches.
Digital Optics
This is a "reformed" optical telecommunications company. That is,
they had a major play in optical components in telecommunications
and the market collapsed. Now they are selling their abilities in
integrated optics to a broader audience. Digital Optics described
their capabilities to create the Photonic Chip platform. This can
include: passive optical components, such as a silicon bench,
diffractive elements, refractive elements, mirrors and other
micro optics, with other active components such as edge emitters,
VCSELs, detectors and electronics all at the wafer level. A major
issue in creating these components is packaging. In the booth
they discussed how the telecommunications market has shifted from
performance as first priority to cost before performance. What
cost $5,000 is now being pushed to $1,500.
Canyon Materials
The product here is HEBS-glass. This is a technology that allows
for the creation of micro optical elements on glass using
traditional photo resist technology. The process begins with an
e-beam writing onto unexposed HEBS-glass. This is then exposed
and creates a grey scale whose variations are on the micron
level. The HEBS-glass is used as a mask with photoresist on the
glass substrate below. The resolution will go to .1 micron per
grey level. When a reactive ionic material is used on the photo
resist structure the result is etching on the glass. This leaves
a micro-optical element. Both refractive and diffractive elements
can be created. The examples shown included the following:
Surface profiles to lambda/10;
Variable f number microlenses on the same array of lenses;
100% fill factor, packed, aspheric microlens arrays;
A 60 micron lens with 24 micron surface depth;
Canyon Materials just makes the HERBS-glass. Its core competency
is the materials and the e-beam writing. The cost of a mask is
determined by the amount of e-beam time needed to create it. It
typically takes 4 - 6 weeks to create a mask. There are from 5 -
10 companies who can take the mask and create the optical
elements. The mask once created is suitable for volume production
in that there should be no wear and tear factors in the
production process. Canyon Materials has 10 employees.
MEMS Optical
This company was showcasing its Grey Scale technology that allows
for the creation of many optical shapes including microlenses,
beam shapers, beam splitters and movable mirrors. In the booth
was a scanning two axis tilt micro-mirror. They also had a free
space optical path length compensator. This was all fabricated on
a single die, which used a variable height surface MEMS surface
to introduce path length compensation. They called this
Continuous Membrane Deformable Mirrors (CMDM). MEMS Optical has a
9,000 sq ft fab facility that supports both MEMS and traditional
silicon wafer processing. They also do front to back alignment in
their photolithography. They will do complete component
fabrication including silicon components or provide services on
wafers that are created in other fabs.
Leister Microsystems
They also make microlens arrays and diffractive structures. The
array sizes can go up to 130mm with array elements to 1mm. The
f/numbers can range from .8 to infinity. Materials include
Silicon, Fused Silica and Plastic. They will also create shims
for injection molding of the components. When I spoke with them
they were clueless about marketing. Defensive on talking about
anything to do with their capabilities - they had no "pitch." I
watched this scenario unfold with a booth walk-up who quickly
walked away wondering what is the story here?
Heptagon
This is a Finnish start-up that creates micro optics. The array
elements range in size from 20 micros to 100 microns and includes
both refractive and diffractive elements. Elements may be created
by e-beam writing or lithography. They have the ability to create
elements on both sides of a surface. In the booth they were
showing an elegant cell phone illumination application of
microlenses. This was a glass surface with many micro optics
lenses, which is used to back light the display. The objective is
to minimize the number of LEDs providing the illumination. This
lens array was lit from the side with the LED and the lens array
created a uniform illumination over the surface of the lens array
for back lighting. The company has a staff of 20.
Nalux
This is a traditional glass and plastic optics company in Japan.
Yet, they see the potential of micro optics. They have developed
technology for micro optics fabrication and created nano-3D
structures in plastic for communications applications. This was
an excellent example of how even a plastic optics company, with
production in China, is moving into these new optics components.
Toyotech
Founded in 1944 this is a optical component company. They have a
facility in China for fabrication. Extensive capabilities in
glass and plastic optics.
Holoeye
This is a Berlin based company that makes, DOE, diffractive
optical elements, which shape and direct beams. The use a polymer
to create the surface profile in glass. The process is
inexpensive and stable. The examples shown in the booth include a
circular pattern of dots that come from a laser that illuminates
the center of the element. I would call this just beam shaping
but Holoeye was excited about the market potential
Advanced Microoptic Systems
This is a German company that makes both diffractive and
refractive micro optics. They use chemical etching to achieve
deep parts which have f/numbers to 1.8. The surface
characteristics are less than lambda/10. Production runs vary
from 100's to 1,000 units. Pricing of a plastic lens array can be
as low as $10. The company has 21 employees and has been in
business 10 years.
Optical Sciences Center, The University of Arizona
OSC has over taken Rochester as the optics center in the US. I
was very impressed with the materials they had describing the
program. Included is an Industrial Affiliates program that seems
to offer some attractive elements of company participation at the
OSC. The program has 100 PhD students and graduates from 10 - 20
per year.
Wave Issue 0205 2/15/02 Article 2-01