Refractive Index Converter
Convert between refractive indices and optical properties
Material Properties
Common optical glass used in lenses and prisms. Has relatively low dispersion compared to flint glass.
Common range: 1.0 (vacuum) to 2.42 (diamond)
Light Properties
Visible light: 380-780nm
Green light at approximately 550nm wavelength. The human eye is most sensitive to this wavelength under normal lighting conditions.
Calculated Optical Properties
Critical Angle:
41.14°
The minimum angle of incidence for total internal reflection
Speed of Light:
1.9723e+8 m/s
65.79% of speed in vacuum
Dispersion Characteristics:
Moderate dispersion - noticeable color separation
Practical Examples
Reflection at Normal Incidence:
When light hits the surface directly (perpendicular), 4.3% of the light is reflected back.
Refraction at 45° Incidence:
Air → Material: Refracted to 27.7°
Material → Air: Total internal reflection
Common Applications:
Common Optical Examples
Understanding Refractive Index
Refractive index (n) is a dimensionless number that describes how light propagates through a medium. It is defined as the ratio of the speed of light in vacuum to the speed of light in the medium.
Key Concepts:
- Snell's Law: n₁sin(θ₁) = n₂sin(θ₂)
- Critical Angle: θc = sin⁻¹(n₂/n₁) where n₁ > n₂
- Total Internal Reflection: Occurs when light tries to pass from a medium with higher n to one with lower n at an angle greater than the critical angle
- Dispersion: Variation of refractive index with wavelength, causing different colors to bend at different angles
Practical Applications:
- Lenses: Focus or diverge light in cameras, microscopes, eyeglasses
- Fiber Optics: Light travels through total internal reflection
- Gemology: Diamond's high refractive index (2.42) creates its brilliant sparkle
- Prisms: Separate light into component colors due to dispersion
- Medical Diagnostics: Refractometers measure concentration of solutions
Abbe Number (Dispersion Measure):
The Abbe number (V) measures how much a material disperses light into its component colors:
Where nᴅ, nF, and nC are the refractive indices at specific wavelengths.
Higher Abbe numbers indicate lower dispersion:
- Crown glass: V ≈ 60
- Flint glass: V ≈ 30
- Polycarbonate: V ≈ 30
- Diamond: V ≈ 44
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Refractive Index Visualization
Critical Angle
41.140°
Reflectivity
4.3%
Brewster's Angle
56.659°
Current Light:
Green (550 nm)
Snell's Law:
n₁ sin(θ₁) = n₂ sin(θ₂)
Optical Effects Explained
Refraction
Light changes
direction when
entering medium
with a different
refractive
index.
The greater the
index
difference,
the more the
light
bends.
Dispersion
Different
wavelengths
(colors) bend
at
slightly
different
angles.
Higher refractive
index materials
typically show
greater
dispersion.
Total Internal Reflection
When light
tries
to exit a
higher
index material
at an angle
greater than
critical angle
it is completely
reflected
internally.
This is the
principle
behind fiber
optics.
Common Materials Refractive Index
| Material | Refractive Index |
|---|---|
| Vacuum | 1.000 |
| Air | 1.000 |
| Ice | 1.310 |
| Water | 1.333 |
| Ethanol | 1.360 |
| Quartz | 1.460 |
| Olive Oil | 1.470 |
| Glycerine | 1.470 |
| Acrylic | 1.490 |
| Crown Glass | 1.520 |
| Emerald | 1.570 |
| Polycarbonate | 1.580 |
| Flint Glass | 1.620 |
| Sapphire | 1.770 |
| Ruby | 1.770 |
| Cubic Zirconia | 2.170 |
| Diamond | 2.420 |
Click on a row to select that material
Optical Phenomena
Total Internal Reflection
Occurs when light travels from a medium with higher refractive index to one with lower index at an angle greater than the critical angle. This phenomenon is the basis for fiber optic communication, prisms, and certain gemstone cuts.
Dispersion
The separation of light into its component colors due to different refractive indices for different wavelengths. This creates the rainbow effect in prisms and the "fire" in diamonds.
Brewster's Angle
The angle of incidence at which light with a particular polarization cannot be reflected. This property is used in polarized sunglasses and optical filters.
About the Refractive Index Converter
Convert between refractive indices and optical properties All conversions run instantly in your browser and nothing you enter is sent to a server.
Common Conversion Formulas
| From | To | Formula |
|---|---|---|
| Refractive Index (n) | Critical Angle (θc) | θc = sin⁻¹(1/n) |
| Refractive Index (n) | Speed of Light in Medium (v) | v = c/n (where c is speed of light in vacuum) |
| Angle of Incidence (θ₁) | Angle of Refraction (θ₂) | n₁sin(θ₁) = n₂sin(θ₂) (Snell's Law) |