MOGlabs MWM, Руководство пользователя, Страница: 9 / 96

1. Introduction
The
MOGL
abs
MWM
optical instrument is a high resolution diffraction grat-
ing spectrometer in Littrow configuration. Optical interference creates an
image of a singlemode fibre core at a wavelength-dependent position on a
semiconductor imaging sensor. The image is digitised at high spatial reso-
lution and with high dynamic range and speed. The wavelength spectrum is
determined from the digitised image and a fitting procedure determines the
peak wavelength. It provides picometre (0.001 nm) accuracy and picowatt
sensitivity, with up to 1250 readings per second. The relative accuracy,
for example in measuring the difference between two laser wavelengths, is
around 10 MHz (0.01pm).
The device can be operated standalone (without a host computer, see
fig. 1.1) or via a web browser (fig. 1.2) or using the
mogwave
GUI
application
(chapter 4). Integration with data acquisition systems is straightforward
using
USB
or ethernet (
TCP/IP
) communications and simple text-based com-
mands.
Figure 1.1:
Wavemeter on-device display, showing serial number, firmware ver-
sion, wavelength range, temperature, pressure, exposure duration and
IP
address.
1.1 Basic setup
1. Connect a 5 V 500 mA power supply via the
USB
interface. Some
computer
USB
ports will provide sufficient power but in general a
dedicated power supply or
USB
hub is recommended.
2. Second and third generation (Rev 2 and later) instruments have
1