Mirror
Mirror is a smooth, highly polished surface, for reflecting light, that may be plane or curved.
The actual reflecting surface is usually a thin coating of silver or aluminum on glass.
YP designs and manufactures a great choice of various high and partially reflecting mirrors for the spectral range: UV, visible, near infrared, and infrared regions. Metallic coatings are more broadband while dielectric coatings are more efficient.
Selecting the proper mirror for your application requires making a number of choices. A few of the many considerations include: Reflectivity, Laser Damage Resistance, Coating Durability, Thermal Expansion of the substrate, Wavefront Distortion, Scattered Light, and certainly Cost. The following tables should help in comparing the available choices from YP.
Featured substrate materials:
Pyrex is an excellent mirror substrate due to its low coefficient of thermal expansion and resistance to thermal shock. When high stability is critical, Zerodur is the best choice for its zero thermal expansion. UV Fused Silica has a thermal expansion coefficient lower than Pyrex, yet is more expensive. Because of its excellent transmissive properties, it is often reserved for transmissive mirrors as well as high-energy laser mirrors.
CZ Silicon is frequently used for laser mirrors because of its high thermal conductivity and low density.
YP can provide Metallic Mirrors and Dielectric Mirrors such as Metal Coated Mirrors, Flate Plates HR Mirrors, Flat Plate Hormnic Separators and other Laser Line Mirrors. The types we supply includes: Plate Mirrors, Spherical Mirrors.
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Material
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Coefficient of Thermal Expansion
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Cost
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Features
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BK7
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7.5 x 10-6/°C
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Low
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High homogeneity and low bubble and inclusion content.
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Pyrex
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3.25 x 10-6/°C
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Low
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Best all around mirror substrate, low expansion borosilicate glass, resistant to thermal shock
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UV Fused Silica
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0.52 x 10-6/°C
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High
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Low thermal expansion for excellent stability, high laser damage resistance
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Zerodur
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0±0.1 x 10-6/°C
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Moderate
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Nominally zero thermal expansion for ultra-high stability, unique glass-ceramic material
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Silicon
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1.20~8.00um
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Moderate
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High thermal conductivity and low density
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Optical surfaces requirements:
The mirror application drives the requirements for surface irregularity and surface quality.
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Surface Flatness
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Figure
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Cost
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Applications
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λ/2
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Low
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Used where wavefront distortion is not as important as cost.
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λ/5
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Moderate
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Excellent for most general laser and imaging applications where low wavefront performance must be balanced with cost.
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λ/10
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Moderate
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For laser and imaging applications where low wavefront distortion, especially in systems with multiple elements.
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λ/20
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High
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For the most demanding laser systems where maintaining accurate wavefront is critical to performance.
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Surface Quality
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Scratch-Dig
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Cost
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Applications
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60-40
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Low
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Used for low-power laser and imaging applications with unfocused beams where scatter is not critical.
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40-20
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Moderate
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Ideal for laser and imaging applications with collimated beams where scatter begins to affect system performance.
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20-10
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High
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Excellent for laser systems with focused beams that can tolerate little scattered light.
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Angle of Incident (AOI):
Usually the Angle of Incident (AOI) are 45 degrees or 0 degree as follows:
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AOI=45°
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AOI=0°
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Manufacturing Tolerances:
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Tolerances
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Commercial quality
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Precision quality
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Manufacturing limits
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Diameter (mm)
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+0/-0.10
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+0/-0.025
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+0/-0.010
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Scratch-Dig
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80-50
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40-20
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10-5
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Power (fringe)
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3
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1
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0.2
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Irregularity (fringe)
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1
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0.5
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0.1
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Parallelism
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-
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3~5 arc min
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Facility controlled
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Bevels
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Upon requirement
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No bevel
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Coatings
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Upon requirement
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YP is an OEM manufacturer, and we don have much standard products in stock. So please contact us for your custom optics. We will do strictly according to your requirements.
Note: Cutting Mirrors, Square Mirrors, Rectangle Mirrors are upon requirement. Plano Mirror, Spherical Mirror, Cylindrical Mirror are upon requirement.
The general tolerance specifications above provide a guideline regarding manufacturing capabilities for optics ranging in size from 1-300mm. The manufacturing limits are not absolute; tighter tolerances may be possible. Part specific tolerances may vary depending on component size, shape, and/or material.