| Penta
Prism |
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| Penta
prism can deviate an incident beam without inverting or
reversing to 90. The deviation angle of 90 is independent
of any rotation of the prism about an axis parallel to the
line of intersection of the two reflecting faces. It is
commonly used in Plumb Level, Surveying, Alignment, Rangefinding
and Optical Tooling. |
| The
deviation angle of 90° is thus independent of the orientation
of the prism, making it especially important in applications
in which the prism orientation cannot be precisely controlled.
Due to geometry that total internal reflection cannot be
used, the reflecting surfaces must be coated with a metallic
or dielectric coating. The standard Penta Prism reflecting
surfaces are coated with aluminum or enhanced aluminum(see
Coating chapter). Sometimes, the coated surfaces are with
black painting.
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| Specifications |
Material:
BK7 Grade A
optical glass
Dimension Tolerance: +/- 0.25mm
90° Deviation Tolerance:
Standard series: < 30 arc seconds
Precision series: up to 10 arc seconds
Flatness:
Standard series: l/2
at 632.8 nm
Precision series: up to l/4
at 632.8 nm
Reflectivity: R > 95% per face from 630 to
680 nm
Surface Quality: 60-40 scratch and dig
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| Beamsplitter
Penta Prism |
| By adding a wedge
and with partial reflective coating, Penta Prism can be
used as Beamsplitter. It is often used in Plumb Level, Surveying,
Alignment, Rangefinding and Optical Tooling. Transmission/reflection
(T/R) ratio of 20/80, 50/50 or others for Beamsplitter Penta
Prism is available upon request. |
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| Specifications |
Material:
BK7 Grade A optical glass
Dimension Tolerance: +/- 0.25 mm
90deg.& 180deg. Deviation Tolerance:
Standard series: < 30 arc seconds
Precision series: up to 15 arc seconds
Flatness:
Standard series: l/2
at 632.8 nm
Precision series: up to l/4
at 632.8 nm
Surface Quality: 60-40 scratch and dig
Beamsplitter Ratio T/R: 20/80 +/-5
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