5
Controls
When the instrument is installed within the Underwater Housing, the touch-screen controls are
accessed via a set of specially-designed, sealed actuator pins (aka plungers), using a design
which has been well-proven in the field.
These plungers are incorporated into the rear acrylic panel (shown in Figure 5).
The plungers are used by the diver to operate the menus on the LCD panel on the rear of the
instrument. This LCD panel incorporates a multi-position, resistive touchscreen. Five plungers
have been provided for the touchscreen. Two additional plungers have been provided to
operate the ON/OFF rocker switch, located on the right-hand side of the instrument rear panel.
One additional plunger is found on the right-hand side of the transparent rear panel, a
waterproof pushbutton switch. This plunger is operated by the diver’s thumb, and has been
incorporated to take spectral scans when the instrument is oriented horizontally.
This brings the total number of plungers to eight. Each plunger head retracts into a counter-
bore on the exterior of the acrylic panel, which serves as a means of limiting the plunger’s
travel. The plungers also have soft tips which contact the screen. Both features have been
incorporated to avoid any damage to the touchscreen. Note that when installed in the provided
tray, the instrument’s LCD touchscreen is always correctly located, so as to accurately align
the plungers with their corresponding LCD touchscreen button locations.
TOUCHSCREEN PLUNGERS
ON/OFF
PLUNGERS
TARGET
ACQUISITION
PLUNGER
Figure 5 Rear Controls (ASM512-500 and ASM1024-500)
