In-Sight
®
1700 Series Wafer Reader Section 3: Configuring a Wafer ID Application
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3.4.9 Light Mode and Light Power
Each Config can have unique Light Mode and Light Power settings for optimizing the
readability of the wafer mark in the image. In-Sight will automatically determine the
optimal light settings for a mark during the tuning process if both the Bright Field and
Dark Field checkboxes in the Tune dialog are enabled.
Light Mode
The Light Mode setting specifies either a Bright Field or a Dark Field illumination effect on
the mark. Each position on the Light Mode slider control enables specific groups of LEDs
to achieve the intended effect in the image.
SELECTION DESCRIPTION
Slider position 0
All lights are disabled. Use this mode only when an external light source is required in a
specialized application.
Slider positions 1-3
(BF1–BF3)
The mark will appear dark on a light background.
Default = BF1
Slider positions 4-12
(DF1–DF8)
The mark will appear light on a dark background.
Light Power
The Light Power setting controls the effective intensity of the LEDs on the mark by
increasing the exposure time of the 1700’s CCD imager, in increments of 0.167
milliseconds. Decrease Light Power for a darker image; increase it for a lighter image.
Generally, use Light Power to maximize the contrast of the mark relative to the
background on the wafer.
NOTE The effect of the Light Power setting is visible in the duration of the “strobed” light pulse as the
reader acquires an image.
3.4.10 Character Spacing
When ‘Chars, SEMI’, ‘Chars, IBM’ or ‘Chars, Triple’ is the selected Mark, the Character
Spacing setting controls the tolerance of the spacing between adjacent characters and
the vertical alignment of the characters. For more information on SEMI Wafer Marking
Specifications, see Appendix H.
NOTE The current Character Spacing setting is used during tuning (Section 3.4.15),
SELECTION DESCRIPTION
Standard Spacing
Reads the characters using standard SEMI specifications for character spacing and vertical
character alignment.
Relaxed Spacing
Reads the characters with more tolerance for deviations from the specifications for character
spacing and alignment.
