ASTM F1595-00(2012)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation: F1595 − 00 (Reapproved 2012)
Standard Practice for
Viewing Conditions for Visual Inspection of Membrane
Switches
This standard is issued under the fixed designation F1595; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 2.1.5 foot–candles—unit of illuminance equal to one lumen
per square foot.
1.1 This practice covers procedures for performing visual
inspection of membrane switches. This includes visual inspec- 2.1.6 membrane switch—a momentary switching device in
tion of overlays and circuitry.
which at least one contact is on, or made of, a flexible
substrate.
1.2 This practice defines lighting parameters, distance from
eye to specimen, viewing angle, and the viewing time allowed
2.1.7 overlay—outer layer of a membrane switch on which
for a specific size specimen. the graphics are printed.
2.1.7.1 Discussion—Not all membrane switches have an
1.3 This practice is only designed for visual inspection of
overlay.
aesthetic qualities of membrane switches. It is not intended for
color matching or gloss measurement.
2.1.8 viewing angle—the angle between the line of sight of
the observer and the surface of the specimen.
1.4 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the
2.1.9 window areas—any area of a membrane switch
responsibility of the user of this standard to establish appro-
through which a display, light, lamp, or other graphics, are
priate safety and health practices and determine the applica-
viewed.
bility of regulatory limitations prior to use.
3. Significance and Use
2. Terminology
3.1 Thispracticeisdesignedtoenableallmanufacturersand
2.1 Definitions:
users of membrane switches to perform visual inspections
2.1.1 aesthetic qualities—these relate to the cosmetic ap-
underuniformconditions.Theaimistoeliminatekeyvariables
pearance of the membrane switch and include such character-
in the inspection procedures so specimens can be viewed more
istics as printing quality, uniformity of finish, material
objectively.
attributes, and mechanical integrity.
3.2 Viewing specimens under these conditions could reveal
2.1.1.1 Discussion—These are often described by such
cosmetic defects in the specimen. Many of these defects or
termsasscratches,bubbles,dents,dings,bumps,blurs,smears,
flaws are due to variables in the raw materials or the manu-
voids,pinholes,etc.Thesearehighlysubjectivetermsthatdefy
facturing process. These cosmetic flaws or defects do not
precise definition but which are nonetheless identifiable and
necessarily mean that the specimen is defective. The determi-
measurable.
nation of whether a specimen is acceptable or defective varies
2.1.2 color matching—procedure by which a color is com-
with the application and the needs of the user. Therefore,
pared to a standard to determine if the two are visually
customer and vendor must agree on acceptable quality stan-
indifferentiable under specified lighting conditions.
dards prior to manufacturing.
2.1.3 continuous scanning motion—viewing technique
3.3 Thispracticedoesnotestablishstandardsforacceptabil-
whereby the inspector views the whole specimen, in the time
ity of specimens, only how they must be viewed (inspected).
allowed, without stopping in any on
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