From: Durston, Tom
[mailto:TDurston@Greenlee.Textron.com]
Sent: Wednesday, November 01, 2006
11:42 AM
To: glen.kramer@TEKNOVUS.COM
Subject: RE: [8023-10GEPON]
10GEPON ad hoc on higher split ratio - Conference Call Minutes
Tom,
Good data. I am not sure why you were not able to post. I
am forwarding this to the reflector (phone and e-mail from you signature were removed
to curb spam).
Glen
Glen, I
tried posting to the listserv but I guess I’ve only got Lurking
permissions. I have some awareness of laser safety as our test products
use Lasers up to 20 mw or so:
As one
might expect Laser Safety is not a simple issue. Requirements are
generally concerned about optical power density (mw/cm^2). I would guess
that an EDFA output at +20 dB (100 mW) could fall under class IIIB.
Revised system
In 2002 the system of Laser Classes was
revised as part of a revision of the international laser safety standard, IEC 60825. The revision was based on the greater
knowledge of lasers that had accumulated since the original classification
system was devised, and was intended to permit certain types of lasers to be
recognized as having a lower hazard than was implied by their placement in the
original classification system. The revised system is expected to be adopted
for use in the
class I
A class 1 laser
is safe for use under all reasonably-anticipated conditions of use; in other
words, it is not expected that the maximum permissible exposure (MPE) can be
exceeded. This class may include lasers of a higher class whose beams are
confined within a suitable enclosure so that access to laser radiation is
physically prevented.
class IM
Class 1M lasers
produce large-diameter beams, or beams that are divergent. The MPE for a Class
1M laser cannot normally be exceeded unless focusing or imaging optics are used
to narrow down the beam. If the beam is refocused, the hazard of Class 1M
lasers may be increased and the product class may be changed.
class II
A class 2 laser
emits in the visible region. It is presumed that the human blink reflex will be
sufficient to prevent damaging exposure, although prolonged viewing may be
dangerous.
class IIM
A class IIM laser
emits in the visible region in the form of a large diameter or divergent beam.
It is presumed that the human blink reflex will be sufficient to prevent
damaging exposure, but if the beam is focused down, damaging levels of
radiation may be reached and may lead to a reclassification of the laser.
class IIIR
A class 3R laser
is a continuous wave laser which may produce up to five times the emission
limit for Class 1 or class 2 lasers. Although the MPE can be exceeded, the risk
of injury is low. The laser can produce no more than 5 mW in the visible
region.
class IIIB
A class 3B laser produces
light of an intensity such that the MPE for eye exposure may be exceeded and
direct viewing of the beam is potentially serious. Diffuse radiation (i.e.,
that which is scattered from a diffusing surface) should not be hazardous. CW
emission from such lasers at wavelengths above 315 nm must not exceed
0.5 watts.
class IV
Class 4 lasers
are of high power (typically more than 500 mW if cw, or 10 J/cm² if
pulsed). These are hazardous to view at all times, may cause devastating and
permanent eye damage, may have sufficient energy to ignite materials, and may
cause significant skin damage. Exposure of the eye or skin to both the direct
laser beam and to scattered beams, even those produced by reflection from
diffusing surfaces, must be avoided at all times. In addition, they may pose a
fire risk and may generate hazardous fumes.
(From The Physical and Theoretical
Tom Durston
Product Development Manager
Greenlee / Textron
From: Glen Kramer
[mailto:glen.kramer@TEKNOVUS.COM]
Sent: Wednesday, November 01, 2006
1:21 PM
To:
STDS-802-3-10GEPON@listserv.ieee.org
Subject: Re: [8023-10GEPON] 10GEPON
ad hoc on higher split ratio - Conference Call Minutes
David,
What about upstream launch power? I
am not sure, but I’d guess the safety rules would be different for CO and
for a household.
Are there any volunteers to make a short overview
presentation on the topic?
Glen
From: David Piehler
[mailto:dpiehler@ALPHION.COM]
Sent: Wednesday, November 01, 2006
6:55 AM
To:
STDS-802-3-10GEPON@listserv.ieee.org
Subject: Re: [8023-10GEPON]
10GEPON ad hoc on higher split ratio - Conference Call Minutes
I don’t know the exact safety issues
involved, but I do know that carriers deploying the video overlay do launch up
to +20 dBm at 1550 nm into the OSP fiber. Also in the CATV world, this
type of launch power is not uncommon.
David Piehler
Alphion
mobile: +1 732 692 4581
From: Glen Kramer
[mailto:
Sent: Tuesday, October 31, 2006
11:49 AM
To:
STDS-802-3-10GEPON@listserv.ieee.org
Subject: Re: [8023-10GEPON]
10GEPON ad hoc on higher split ratio - Conference Call Minutes
Mike,
This is a great point. Could you provide
some more info on class 1 safety? In general, what regulations apply to
CPE side and to CO side? It would be great to have a presentation in
November covering this topic. It definitely should be part of the set of
constraints that the high-split ad hoc considers.
Glen
From:
Sent: Tuesday, October 31, 2006
11:35 AM
To:
STDS-802-3-10GEPON@listserv.ieee.org
Subject: Re: [8023-10GEPON]
10GEPON ad hoc on higher split ratio - Conference Call Minutes
Dear
all,
One
question related to the higher split ratio that I haven't seen discussed is
related to laser eye safety. Is this a problem for
EPON? For other ethernet standards we've normally required class 1
eye safety. I think powers significantly higher than
this are being considered here.
Regards,
Director Transceiver
Engineering
Picolight Inc
CO 80027
Tel 303 530 3189 x7533.
mike.dudek@picolight.com
From:
Sent: Tuesday, October 31, 2006 1:06 AM
To: STDS-802-3-10GEPON@listserv.ieee.org
Subject: [8023-10GEPON] 10GEPON ad hoc on higher split ratio - Conference Call
Minutes
Dear
all,
below
please find the conference call minutes, taken down by Glen (thank You for the
job well done)
please
let me know if You find any irregularities in the minutes or if You have any
comments on those.
*******************************************************************************
Attendees:
Haim Ben-Amram
Russell Davey
Glen Kramer
Marek Hajduczenia
Frank Chang
Silvia Pato
David Piehler
Harold Kamisugi
Bin Yeong Yoon
Dong Soo Lee
Wael Diab
Task 1: estimation of 1x64
and 1x128 port splitter power loss values
---------------------------------------------------------------------
Discussed Marek's
presentation. Few questions about derivation of splitter loss. No objections.
Task 1 is considered completed.
Task 2: non-linear effects in
fiber channel
-------------------------------------------
Silvia gave brief overview of
the paper on non-liner effects in 10GEPON. SBS seems like major impairment.
Mentioned dithering technique for laser sources.
Questions that need more
research:
1) Can video-overlay even be
supported on 1x128 PON? What power budget will be required?
2) Can we use high-power
source for data wavelength and use video-overlay? Effects of Raman crosstalk
due to high-power source.
AR: Silvia will finish
sub-task 2.2 "estimate the maximum launch power into fiber which can be
achieved without introducing non-linear effects" by November 6th.
Task 3: TX/RX technology
----------------------
Bin Yeong Yoon and dong Soo
Lee are in the process of compiling a survey of receivers, transmitters, and amplifiers
available on the market today.
AR: Bin Yeong Yoon is to
finish the first draft later this week. Then narrow down the viable
configurations based on input from task 2.
Task 4: power margins in the
EPON systems
-----------------------------------------
It seemed to be difficult to
get this data from carriers. It was decided that for now we will
reverse-calculate this data from insertion loss taken in 802.3ah. We later may
update it with more accurate numbers based on carriers' responses to a wavelength/power
survey.
AR: Marek is to calculate
allocation for penalties and outside plant aging and repair margins later this
week.
An additional conference call
may be scheduled to discuss final drafts of the presentations.
*******************************************************************************
Best
wishes
Marek
Hajduczenia (141238)
(PhD Student - COM RD1)
SIEMENS
Networks S.A. - IC
Rua Irmãos Siemens, 1
Ed. 1, Piso 1
Alfragide
2720-093 Amadora
Portugal
* Marek.Hajduczenia@siemens.com
http://marekhaj.easyisp.pl/index.php
(+351.21.416.7472 4+351.21.424.2082
