Intevac MicroVista NIR User manual

Intevac, Inc.
3560 Bassett Street
Santa Clara, CA
95054-2704
MicroVista®NIR and UV Cameras
User Manual
User Manual

MicroVista Camera User Manual ICD0057 Rev 1
2 Imaging Support: imagin[email protected] http://www.mosir950.com 408-496-2019
1WARNINGS AND SAFETY PRECAUTIONS
Electric Shock Hazard
Static Electricity
IMPORTANT: Any changes or modifications not expressly approved in this
manual may void the manufacturer’s warranty.
This symbol is intended to alert the user to the presence of important operating
and maintenance (servicing) information in the literature accompanying the
appliance.
To prevent fire or shock hazard, do not expose the unit to rain or moisture.
The components in this camera are susceptible to static electricity. Do not open
camera. There are no user serviceable parts inside. Contact Intevac, Inc. for
any problems or repairs.

MicroVista Camera User Manual
Imaging Support: [e-mail] http://www.mosir950.com 408-496-2019 3
In Case of Problem
Handle with Care
Cleaning
Protect from High Temperatures
Do Not Open or Modify
Protect from Humidity and Dust
Do not use the camera if smoke (or a strange odor) emanates from the unit, or
if there are any other apparent electrical problems. Disconnect the power cable
immediately and consult the manufacturer (or authorized reseller).
Proper care should be taken when transporting or handling the camera.
Prolonged vibration, or dropping the camera can damage components.
Dirt may be removed from the exterior case by wiping it with a soft cloth. To
remove stains, wipe with a soft cloth lightly moistened with a gentle detergent
solution. Wipe with a dry cloth after cleaning. Do not use a benzene, thinner, or
other chemical product on the camera case, as that may cause discoloration or
deformation.
Do not install close to heat generating devices, such as spotlights or
generators, etc. Install where the temperature range is between -10°C and
40°C.
Do not open the camera case, as it may be dangerous and cause damage to
the unit. For internal settings and repairs, consult the manufacturer (or Intevac
authorized reseller).
To prevent camera damage, do not install it where there is smoke or steam,
where dampness may reach high levels, or where there is excessive dust.

MicroVista Camera User Manual ICD0057 Rev 1
4 Imaging Support: imagin[email protected] http://www.mosir950.com 408-496-2019
2CAMERA OVERVIEW
Introduction
MicroVista®cameras are back-illuminated CMOS cameras optimized for
ultraviolet (UV) and near-infrared (NIR) response. The combination of 100% fill-
factor and high Quantum Efficiency (QE) from proprietary coatings provides
sensitivity comparable to scientific-grade CCD cameras. The MicroVista®camera
has a 1.3 megapixel resolution and 30 frames per second full frame digital
readout via CameraLink. The camera has a small form factor, low power
consumption, and is ideal for high sensitivity video rate imaging.
Camera Features
•Image
•Programmable AGC
•Windowing (Region of Interest)
•Image Orientation (Horizontal Flip)
•Digital Zoom
•Histogram Equalization
•Software Interface
•Windows XP and Windows 2000
•MicroVista®GUI Application
•MicroVista®SDK
•Hardware Interface
•CameraLink for video output
•RS-232 or CameraLink for camera control

MicroVista Camera User Manual
Imaging Support: [e-mail] http://www.mosir950.com 408-496-2019 5
•Power Consumption: 2 Watts @ 3.6 VDC
•Camera Description
•Lens Interface: C-mount, 1" optical format
•Camera Mount: 1/4"-20
•Exposure Range: 30 μsec to 6 seconds (Rolling Shutter), 30 μs to
270 ms (Pseudo-Snapshot)
•Shutter Type: Rolling
CMOS Operation
Rolling Shutter
MicroVista®operates in a mode called Rolling Shutter. It is the most common
mode of readout for CMOS imaging devices. In Rolling Shutter readout mode,
each row of the sensor is accessed sequentially from the first to the last row. After
each row is read out, it is reset before it starts integrating the next exposure.
When the reset period ends, the row integrates light until it is addressed again in
the next image frame. The time interval from row to row is constant, so all rows
receive the same amount of exposure time, but the readout is sequential, so the
rows are not all exposed simultaneously.
The length of time that the row is held in reset determines the exposure time for
that row. A row with a very short reset period will have a relatively long exposure
period, and vice versa. For example, running at 30 frames per second gives a
readout time of 33.33 milliseconds per frame. If there are 1024 rows, then each
row will require 0.03 ms to read out. If each row is subsequently held in reset for
23.33 ms, then each row will have 10 ms of exposure per frame. (The minimum
reset time for the MicroVista®CMOS device, also known as the row blanking time,
is 3.45 µs.)
Pseudo-Snapshot
It is possible for a rolling shutter device to emulate a snapshot shutter device by
using a modification of the readout called Pseudo-Snapshot. Normally, a Rolling

MicroVista Camera User Manual ICD0057 Rev 1
6 Imaging Support: imagin[email protected] http://www.mosir950.com 408-496-2019
Shutter device goes immediately from the last row of a frame to the first row of the
next frame. In Pseudo-Snapshot mode, the device instead waits for a period of
time after reading the last row before starting the first row of the next frame.
During this waiting period, the entire device is being exposed at the same time,
like a snapshot shutter. After the waiting period, rolling shutter readout resumes.
For example, a MicroVista®is put in Pseudo-Snapshot mode with an exposure
time of 50 ms. The Rolling Shutter readout time for the MicroVista®is 33.33 ms. If
the frame begins at time 0, then the first row will be exposed for time t=0.00 to
t=50.00 ms; the second row will be exposed for time t=0.03 to t=50.03 ms, and the
last row will be exposed for time t=33.30 to t=83.30 ms. From time t=33.30 to
t=50.00 ms, all rows are exposing at the same time.
Motion Artifacts
Due to the way rolling shutter reads out, it is susceptible to certain motion
artifacts. Since each row sees a slightly different time slice, fast moving objects
can get stretched out. Objects moving from left to right or right to left will be
slanted in the direction of motion. Objects moving from top to bottom will be
elongated, and objects moving from bottom to top will be shortened.
Rolling Shutter Frame Rate
In Rolling Shutter mode, it is possible to lower the frame rate (increase exposure
time) without resorting to Pseudo-Snapshot mode. Increasing the interline delay
(reset time for each row) will increase the time it takes to go from one row to the
next, and thus the total readout time for a frame. For example, the minimum row
blanking time of 3.45 μs plus the 29.09 μs of row readout gives a frame rate of 30
fps (33.33 ms) for 1024 rows. Increasing the row blanking time to 166.23 μs will
increase the readout time to 200.01 ms for 1024 rows for a frame rate of 5 fps.
Windowing
The MicroVista®is capable of changing the size of the image area that is read out.
Setting a specific window in the image allows the camera to read out that
particular portion of the image area at a much higher frame rate than a full frame.
The size and location of the window are defined by the starting row and column
and ending row and column of a rectangle. The only restrictions on the window
parameters are that the starting and ending column must be between 1 and 1280
and divisible by 8, and the starting and ending row must be between 1 and 1024.

MicroVista Camera User Manual
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To calculate the readout time of a particular window, use the following equation:
The following table lists readout times and frame rates for some common window
sizes:
Window Size Readout Time Frame Rate
1280 x 1024 33327 µs 30 Hz
640 x 512 9216 µs 109 Hz
320 x 256 2746 µs 364 Hz
160 x 128 908 µs 1102 Hz
80 x 64 337 µs 2963 Hz
tread = ((colend -col
start + 1) ×tpixel + treset)×(rowend - rowstart +1)
treset = 152 ×tpixel = 3.4545 µs
tpixel = ----------- = 0.0227 µs
1
44 MHz

MicroVista Camera User Manual ICD0057 Rev 1
8 Imaging Support: imagin[email protected] http://www.mosir950.com 408-496-2019
Camera Specifications
Video Communication: CameraLink and RS-232
Power Consumption: 2 Watts at 3.6 VDC
Cooling: Passive air cooling (no fan required)
Image Device: Back illuminated CMOS, anti-reflection coating to optimize
near infrared (NIR) or UV response (depending on model)
Image Size: 13.8 x 11.06 mm; 17.7 mm diagonal
Resolution: 1.3 million pixels (1280 x 1024)
Pixel Size 10.8 µm square
Fill Factor: 100%
System Read Noise: 40 e-rms (typical)
Spectrometric Well Capacity: 40 ke-(typical)
Dark Current: 150 e-/p/s (typical)
Lens Mount: C-mount, 1” optical format
Camera Mount: 1/4"-20
Shutter Type: Rolling
Exposure Range: 30 µs to 6 seconds, depending on region of interest (ROI)
ROI (Windowing): Software selectable
Frame Rate vs. ROI: 1280 x 1028: 30 fps
512 x 512: 29 fps
128 x 128: 1230 fps
Digital Output Bit Depth: 10 bit monochrome
Environmental: Operating Temperature: 0°C to +50°C
Humidity: 5% to 95% non-condensing
Weight: 225 grams
Dimensions (WxHxD): 2" x 2" x 3"

MicroVista Camera User Manual
Imaging Support: [e-mail] http://www.mosir950.com 408-496-2019 9
QE Response Curve
Figure 1: QE Response Curve of MicroVista®UV Camera
Figure 2: QE Response Curve of MicroVista®NIR Camera
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Quantum Efficiency (%)
VU
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Quantum Efficiency (%)
RI

MicroVista Camera User Manual ICD0057 Rev 1
10 Imaging Support: imagin[email protected] http://www.mosir950.com 408-496-2019
Camera Dimensions
Figure 3: Camera Dimensions