IR distance ranger covers 1 to 20 cm:
04/11/2002 EDN - Design Ideas / Commercially
available IR distance rangers typically handle a 3-
to 30-in. detection distance. Many times, it is
necessary to determine smaller distances. The
circuit in Figure 1 is useful for measuring small
distances to reflective surfaces. Its measurement
range is from less than 1 cm to approximately 20 cm
for a flat, white surface. .
