J. Tyson 2004-2007. Last updated 02-05-07.
| project: night vision windshield |
Find something and burn it
| Part I - The camera. |
Picture of a monitor displaying the
image of a white and fluorescent
orange pistol target at 25 feet in a
darkened room. Unfortunately,
focus and resolution aren't nearly
as good as I had expected due to
the physical limitations of the focus
ring threads on the camera.
In the next few days I'm going to
attempt to hunt down a cheapo
webcam lens in hopes that the
shorter focal length will allow me to
shorten the coupling bracket and
also optimize the focus at the
phosphor screen.
Last entry - 28-01-2008.
image of a white and fluorescent
orange pistol target at 25 feet in a
darkened room. Unfortunately,
focus and resolution aren't nearly
as good as I had expected due to
the physical limitations of the focus
ring threads on the camera.
In the next few days I'm going to
attempt to hunt down a cheapo
webcam lens in hopes that the
shorter focal length will allow me to
shorten the coupling bracket and
also optimize the focus at the
phosphor screen.
Last entry - 28-01-2008.
The adjustable camera coupling
was fabricated from aluminum heat
sink scraps. The camera was
squared to the tube lens and then
epoxied to the rear bracket to
ensure precise alignment before
drilling the mounting screw holes.
Here the completed imaging
section is powered up for initial
focus adjustments. It had not
occurred to me before this point to
actually check that the tube
worked. I was relieved to find that It
does. Much to my chagrin
however, the focused assembly is
now exactly 1/8 of an inch longer
than the enclosure intended to
house it. Whoops.
was fabricated from aluminum heat
sink scraps. The camera was
squared to the tube lens and then
epoxied to the rear bracket to
ensure precise alignment before
drilling the mounting screw holes.
Here the completed imaging
section is powered up for initial
focus adjustments. It had not
occurred to me before this point to
actually check that the tube
worked. I was relieved to find that It
does. Much to my chagrin
however, the focused assembly is
now exactly 1/8 of an inch longer
than the enclosure intended to
house it. Whoops.
Mock up of the 54 x 120mm lens
and bezel installed in the aluminum
hobby enclosure.
Of note: This lens was destroyed
as a result: Aluminum filings un
noticeably fouled the fine pot metal
threads during installation making
non destructive removal
impossible. The lens was finally
removed using two pipe wrenches
with predictably disastrous results.
Luckily I had a second lens and a
lesson was learned. All cut
surfaces have since been
deburred with fine emery paper
and threaded pieces are blown
with compressed air before and
after every mating.
and bezel installed in the aluminum
hobby enclosure.
Of note: This lens was destroyed
as a result: Aluminum filings un
noticeably fouled the fine pot metal
threads during installation making
non destructive removal
impossible. The lens was finally
removed using two pipe wrenches
with predictably disastrous results.
Luckily I had a second lens and a
lesson was learned. All cut
surfaces have since been
deburred with fine emery paper
and threaded pieces are blown
with compressed air before and
after every mating.
Lens and bezel installed into the
enclosure to test fitment. The
surveillance camera is a
reasonable quality 480 line NTSC
colour CCD video camera bought
from dealextreme for the princely
sum of $12.
To the right of the camera are the
high voltage inverter required to
operate the tube and a pair of
near infrared emitters that will
illuminate the road for the image
intensifier tube.
enclosure to test fitment. The
surveillance camera is a
reasonable quality 480 line NTSC
colour CCD video camera bought
from dealextreme for the princely
sum of $12.
To the right of the camera are the
high voltage inverter required to
operate the tube and a pair of
near infrared emitters that will
illuminate the road for the image
intensifier tube.
The remains of this sad pair of
night vision binoculars (right)
rescued from the bottom of the
manufacturer's dumpster will
donate the first generation image
intensifier (a.k.a. 'night vision')
tube and funky 54 x 120mm
objective lens for my latest oddball
project: A futuristic night vision
windshield display for the beast to
allow for rural 'lights off' night
driving - Just because.
The experiment involves building a
forward facing night vision video
camera that will be mounted to the
truck's roof. The video feed will
then be routed into the cab where
a CRT monitor modified to display
a mirrored left-to-right image will
be mounted in the midship
bulkhead also facing forward. A
lens assembly scavenged from a
rear projection screen TV will then
project the image over the driver's
right shoulder forward, onto the
inside surface of the windshield.
Electronically, this is a simple and
straightforward project. Success or
failure will depend on the ability to
correct for parallax so that the
image displayed on the windshield
will appear to overlay the normal
view, accurately representing the
road position from the driver's
normal perspective.
The camera will be constructed by
coupling a small video surveillance
camera to the phosphor screen of
the image intensifier tube inside a
light tight enclosure with
appropriate power supplies to
operate the tube and camera from
the vehicle's 12V electrical system.
Once proof of concept has been
established I'll revisit the camera's
electronics and fashion additional
auto iris and AGC circuitry as
required.
In order to maintain the physical
relationship of the tube's
photocathode and objective lens I
decided to use the entire 'front
end' of the binocular intact. A little
bit of angle grinder surgery (above
right) was performed to cut the
bezel to suitable dimensions.
night vision binoculars (right)
rescued from the bottom of the
manufacturer's dumpster will
donate the first generation image
intensifier (a.k.a. 'night vision')
tube and funky 54 x 120mm
objective lens for my latest oddball
project: A futuristic night vision
windshield display for the beast to
allow for rural 'lights off' night
driving - Just because.
The experiment involves building a
forward facing night vision video
camera that will be mounted to the
truck's roof. The video feed will
then be routed into the cab where
a CRT monitor modified to display
a mirrored left-to-right image will
be mounted in the midship
bulkhead also facing forward. A
lens assembly scavenged from a
rear projection screen TV will then
project the image over the driver's
right shoulder forward, onto the
inside surface of the windshield.
Electronically, this is a simple and
straightforward project. Success or
failure will depend on the ability to
correct for parallax so that the
image displayed on the windshield
will appear to overlay the normal
view, accurately representing the
road position from the driver's
normal perspective.
The camera will be constructed by
coupling a small video surveillance
camera to the phosphor screen of
the image intensifier tube inside a
light tight enclosure with
appropriate power supplies to
operate the tube and camera from
the vehicle's 12V electrical system.
Once proof of concept has been
established I'll revisit the camera's
electronics and fashion additional
auto iris and AGC circuitry as
required.
In order to maintain the physical
relationship of the tube's
photocathode and objective lens I
decided to use the entire 'front
end' of the binocular intact. A little
bit of angle grinder surgery (above
right) was performed to cut the
bezel to suitable dimensions.
A 56.5mm round hole (above right)
was meticulously hand cut to just
pass the lens threads so that the
thin lens spacer ring would retain
the assembly by sandwiching the
enclosure panel between the ring
and thread shoulder (right).
was meticulously hand cut to just
pass the lens threads so that the
thin lens spacer ring would retain
the assembly by sandwiching the
enclosure panel between the ring
and thread shoulder (right).