Reflection Calculator
Results:
What is Reflection Calculator?
A reflection calculator is a physics tool that calculates the angle of reflection, reflectance, and critical angle when light hits a surface between two different media. Based on the law of reflection, the angle of incidence equals the angle of reflection.
This calculator uses Fresnel equations to determine reflectance and can identify total internal reflection conditions when light travels from a denser to a less dense medium.
How It Works
Enter Parameters
Input incident angle and refractive indices
Apply Physics Laws
Uses Fresnel equations and reflection laws
Get Results
Reflection angle, reflectance, and critical angle
Common Examples
Air to Glass
Light traveling from air (n=1.0) to glass (n=1.5)
- • Incident angle: 30°
- • Reflection angle: 30°
- • Reflectance: ~4%
Glass to Air
Light traveling from glass (n=1.5) to air (n=1.0)
- • Critical angle: 41.8°
- • Total internal reflection above critical angle
- • Used in optical fibers
Calculation Table
| Medium 1 → Medium 2 | n₁ | n₂ | Critical Angle | Normal Reflectance |
|---|---|---|---|---|
| Air → Glass | 1.00 | 1.50 | N/A | 4.0% |
| Glass → Air | 1.50 | 1.00 | 41.8° | 4.0% |
| Water → Air | 1.33 | 1.00 | 48.6° | 2.0% |
| Diamond → Air | 2.42 | 1.00 | 24.4° | 17.0% |
Frequently Asked Questions
What is the law of reflection?
The law of reflection states that the angle of incidence equals the angle of reflection, and both angles are measured from the normal to the surface.
What is total internal reflection?
Total internal reflection occurs when light travels from a denser medium to a less dense medium at an angle greater than the critical angle, causing 100% reflection.
How is reflectance calculated?
Reflectance is calculated using Fresnel equations, which consider the refractive indices of both media and the angle of incidence to determine the percentage of reflected light.
What are common refractive indices?
Air: 1.00, Water: 1.33, Glass: 1.5, Diamond: 2.42. These values determine how light bends and reflects at interfaces between different materials.
Is this calculator accurate?
Yes, this calculator uses precise physics formulas including Fresnel equations and Snell's law to provide accurate reflection calculations for optical applications.