Specular reflection is the
mirror-like reflection of light from
a surface, in which light from a single incoming
(a ray) is reflected into a single outgoing
This is in contrast to diffuse reflection,
light is reflected in a broad range of directions.
foils have naturally smooth surfaces, even at the microscopic level, offering
each individual ray of light the same surface orientation. As such, reflective
foils are a natural specular reflective material.
microscopic geometry of ORCA Grow Film® microfiber and pore structure provides
a rough surface, offering each individual ray of light a different surface
orientation. As such, ORCA Grow Film® is a natural diffuse reflective
Why Diffuse Reflection Matters:
spots or flash points occur when bundles of concentrated light rays which are
traveling parallel to each other converge. In hydroponic grow rooms, the hot
spot phenomenon is dramatically increased when using a material with a specular
reflection as a supplementary lighting source to the grow lamps.
A light beam can be thought of as a bundle of individual light rays which are
traveling parallel to each other. Each individual light ray of the bundle
follows the law of reflection. If the bundle of light rays are incident upon a
smooth surface, then the light rays reflect and remain concentrated in a bundle
upon leaving the surface.
Changes in the orientation of a specular reflective surface, can cause
concentrated light rays to converge together either on their first or
subsequent bounces. Hot spots or flash points occur when the direction of these
concentrated light rays converge together.
In a grow room
environment, orientation changes are commonly associated with corners and
angles where walls, floors, and ceilings meet. Static objects in the grow room
like duct work, equipment, tools, and planters can also contribute on
subsequent bounces. Regardless of the grow room layout, the use of a specular
reflective material on the walls, ceiling, and floors as a supplement lighting
device to your grow lamps will be the biggest contributor to hot spots.
Foils produce a specular
reflection and therefore need to be hung on a wall with an absolutely
flat/smooth orientation. Any creasing or ripples in the material either as a
result of installation, or due to manufacturing imperfections, increase changes
in the orientation of the specular reflection, causing the concentrated light
rays to converge, thus promoting hot spots.
other hand, if the surface is microscopically rough, the light rays will
reflect and diffuse in many different directions. The microscopic geometry of
the ORCA Grow Film® microfibers and pores means that each individual
ray meets a surface which has a different orientation.
The normal line at the point of incidence is different for different rays.
Subsequently, when the individual rays reflect off the rough surface according
to the law of reflection, they scatter in different directions. The result is
that the rays of light are incident upon the surface in a concentrated bundle
and are diffused upon reflection. Not only does a natural diffuse
reflecting surface eliminate hot spots, you no longer need to worry about the
product being installed on an absolutely flat/smooth orientation. The
number and types of corners, angles, static objects found in your grow room
layout may still reduce overall efficiency, but the efficiency will be greater
because of the improved distribution from subsequent bounces off the reflecting
surface. Less hotspots means more efficient utilization of your light.
Some manufacturers attempt to reduce the specular nature of their foil and the
resulting hot spots by embossing the foils surface. They “scratch” or “strike”
the surface with a diamond pattern to create a surface that is partially rough.
While this process creates a partial diffuse effect, it does not change the
inherit specular nature of the material, the surface, or the resulting
Every gardener knows
to use the right tool for the right job. Why would you consider using an
underperforming specular foil, or one that has been “scratched” in attempt to
act diffuse, when there is a high performance option with the natural diffuse
reflection your plants desire?
You no longer need to “foil” your grow
room; advancements in technology have delivered the right tool. – ORCA Grow Film®.