Mathematics · Trigonometry
Optical Numerical Aperture Calculator
Calculate numerical aperture from refractive index of object space and acceptance half-angle in degrees.
Inputs and results stay in this browser. Change one value at a time to explore the relationship.
Calculation steps
- Use c=a sin(b) with refractive index of object space=1.33 and acceptance half-angle in degrees=48.
- numerical aperture=0.9883826178849344.
Understand Optical Numerical Aperture
One idea, three depths
Choose how deeply to explain Optical Numerical Aperture
Optical Numerical Aperture: Calculate numerical aperture from refractive index of object space and acceptance half-angle in degrees.
Age 5Explain it to a 5-year-oldStart with a picture
Imagine using Optical Numerical Aperture to answer this question: calculate numerical aperture from refractive index of object space and acceptance half-angle in degrees? Enter refractive index of object space and acceptance half-angle in degrees; the calculator shows numerical aperture. For example: refractive index of object space=1.33 and acceptance half-angle in degrees=48 produce numerical aperture=0.9883826178849344. The answer tells you numerical aperture.
Age 15Explain it to a 15-year-oldConnect it to the formula
Optical numerical aperture equals object-space refractive index multiplied by sine of the acceptance half-angle. This page evaluates the relationship directly. The rule is c=a sin(b). Its input values are refractive index of object space, acceptance half-angle in degrees, and the main result is numerical aperture. For example: refractive index of object space=1.33 and acceptance half-angle in degrees=48 produce numerical aperture=0.9883826178849344.
CollegeExplain it at college levelState the model precisely
This calculator evaluates the stated optical numerical aperture relation over the valid real-number domain stated below. The implemented relation is c=a sin(b), evaluated from refractive index of object space, acceptance half-angle in degrees to produce numerical aperture. Optical numerical aperture equals object-space refractive index multiplied by sine of the acceptance half-angle. This page evaluates the relationship directly. Use the medium at the entrance pupil and the correct half-angle; aberrations, immersion mismatch, wavelength, pupil filling, and paraxial assumptions affect performance.
Inputs and valid domain
- refractive index of object space must be a finite real number.
- acceptance half-angle in degrees must be a finite real number.
Important boundary: Use the medium at the entrance pupil and the correct half-angle; aberrations, immersion mismatch, wavelength, pupil filling, and paraxial assumptions affect performance.
The formula
c=a sin(b)
How the calculator works through it
It substitutes refractive index of object space, acceptance half-angle in degrees into the formula and exposes every numerical step above. The main output is numerical aperture.
Read the result correctly
The numerical aperture is the direct answer to “calculate numerical aperture from refractive index of object space and acceptance half-angle in degrees.” Read it with the units shown beside the inputs; a sign, angle, percentage or rate changes what the number means.
A worked check
refractive index of object space=1.33 and acceptance half-angle in degrees=48 produce numerical aperture=0.9883826178849344.
Where this model stops being reliable
Use the medium at the entrance pupil and the correct half-angle; aberrations, immersion mismatch, wavelength, pupil filling, and paraxial assumptions affect performance.
Learn it by changing one value
Begin with the worked example, then change one value while keeping the others fixed. Compare the new result and calculation steps to identify which part of the formula changed.
Dictionary terms behind this calculator
Before studying the codeWhat you should know firstUse the calculator immediately, or check the foundations before reading the implementation.
These foundations help you understand why Optical Numerical Aperture works. They never block the calculator, and “optional” means useful context rather than a hidden requirement.
Hard requirements
- Reading formulas and substituting values
Optical Numerical Aperture uses c=a sin(b). You need to recognise what each side represents before substituting the stated inputs or rearranging the relationship.
Review this foundation about 4 min
Strong support
- Angles in degrees and radians
Interpreting the angle convention is essential for understanding the inputs and output of Optical Numerical Aperture.
Review this foundation about 5 min
Optional enrichment
- Functions and their graphs
Function graphs show how the Optical Numerical Aperture relationship changes across a full angle or period.
Review this foundation about 6 min
Mathematics → algorithm → program
Implement this calculation in code
These are direct reference implementations of the calculator's principal relationship and first output. They run locally and include a small known-answer check where the language supports it.
Algorithm
- Read refractive index of object space, acceptance half-angle in degrees.
- Evaluate the principal relationship: c=a sin(b).
- Return numerical aperture and check the domain conditions described above.
Python
from math import *
def optical_numerical_aperture_calculator(a, b) -> float:
return (a * sin(((b * pi) / 180.0)))
assert abs(optical_numerical_aperture_calculator(1.33, 48) - 0.9883826178849344) < 1e-6 * max(1.0, abs(0.9883826178849344))
C
#include <assert.h>
#include <math.h>
double optical_numerical_aperture_calculator(double a, double b) {
return (a * sin(((b * 3.141592653589793) / 180.0)));
}
int main(void) {
const double expected = 0.9883826178849344;
const double actual = optical_numerical_aperture_calculator(1.33, 48);
assert(fabs(actual - expected) < 1e-6 * fmax(1.0, fabs(expected)));
}
C++
#include <cassert>
#include <cmath>
#include <numbers>
double optical_numerical_aperture_calculator(double a, double b) {
return (a * std::sin(((b * std::numbers::pi) / 180.0)));
}
int main() {
constexpr double expected = 0.9883826178849344;
const double actual = optical_numerical_aperture_calculator(1.33, 48);
assert(std::fabs(actual - expected) < 1e-6 * std::fmax(1.0, std::fabs(expected)));
}
Linux x86-64 assembly
x86-64 NASM · System V ABI · Linux · SSE2 with libm where required
; double optical_numerical_aperture_calculator(double a, double b)
; Linux x86-64 NASM · System V ABI · first eight doubles in xmm0–xmm7
extern sin
global optical_numerical_aperture_calculator
section .text
optical_numerical_aperture_calculator:
push rbp
mov rbp, rsp
sub rsp, 64
movsd [rbp-8], xmm0
movsd [rbp-16], xmm1
mov rax, 0x400921fb54442d18
movq xmm0, rax
movsd [rbp-56], xmm0
movsd xmm0, [rbp-16]
mulsd xmm0, [rbp-56]
movsd [rbp-48], xmm0
mov rax, 0x4066800000000000
movq xmm0, rax
movsd [rbp-64], xmm0
movsd xmm0, [rbp-48]
divsd xmm0, [rbp-64]
movsd [rbp-40], xmm0
movsd xmm0, [rbp-40]
call sin wrt ..plt
movsd [rbp-32], xmm0
movsd xmm0, [rbp-8]
mulsd xmm0, [rbp-32]
movsd [rbp-24], xmm0
movsd xmm0, [rbp-24]
leave
ret
MATLAB
function result = optical_numerical_aperture_calculator(a, b)
result = (a * sin(((b * pi) / 180.0)));
end
Wolfram Language
ClearAll[mwCalculate];
mwCalculate[a_, b_] := (a * Sin[((b * Pi) / 180.0)]);
Continue in mathematical software
The downloaded file includes your current inputs and first calculated result. It is created locally.
Floating-point answers can differ slightly by language, compiler and processor. Compare within a suitable tolerance rather than assuming every decimal representation will be identical.
Supporting sourcesAcademic referencesPrimary standards, textbooks and complete citations
Standards, reading and academic references
Use the calculator as the worked interaction, then consult the primary standards and academic textbooks listed below. MW SysArc links to the original sources; the explanation on this page is original and does not reproduce them.
Algebra and Trigonometry 2e
Read the related free OpenStax mathematics chaptersCite this book
- APA 7
- Abramson, J. (2021). Algebra and trigonometry 2e. OpenStax. https://openstax.org/books/algebra-and-trigonometry-2e/pages/1-introduction-to-prerequisites
- MLA 9
- Abramson, Jay. Algebra and Trigonometry 2e. OpenStax, 2021, https://openstax.org/books/algebra-and-trigonometry-2e/pages/1-introduction-to-prerequisites.
- Chicago author-date
- Abramson, Jay. 2021. Algebra and Trigonometry 2e. Houston, TX: OpenStax. https://openstax.org/books/algebra-and-trigonometry-2e/pages/1-introduction-to-prerequisites.
OpenStax entries are free to read online. Follow the licence shown on each linked source before redistributing or adapting its content.
Reuse the page responsiblyCite this pageAPA, MLA, Chicago, Harvard, BibTeX and RIS
These formats cite this calculator page itself. They are separate from the academic references above, which support the mathematical method and terminology.
APA 7
MW SysArc. (2026, July 21). Optical Numerical Aperture Calculator. MW SysArc Tools. https://math.mwsysarc.com/trigonometry/optical-numerical-aperture-calculator
MLA 9
MW SysArc. “Optical Numerical Aperture Calculator.” MW SysArc Tools, 21 July 2026, https://math.mwsysarc.com/trigonometry/optical-numerical-aperture-calculator. Accessed 31 Aug. 2026.
Chicago 17
MW SysArc. “Optical Numerical Aperture Calculator.” MW SysArc Tools. Published July 21, 2026. Accessed August 31, 2026. https://math.mwsysarc.com/trigonometry/optical-numerical-aperture-calculator.
Harvard
MW SysArc (2026) ‘Optical Numerical Aperture Calculator’, MW SysArc Tools. Published 21 July 2026. Available at: https://math.mwsysarc.com/trigonometry/optical-numerical-aperture-calculator (Accessed: 31 August 2026).
BibTeX and RIS records
BibTeX
@misc{mwsysarc_optical_numerical_aperture_calculator_2026,
author = {{MW SysArc}},
title = {Optical Numerical Aperture Calculator},
howpublished = {MW SysArc Tools},
year = {2026},
url = {https://math.mwsysarc.com/trigonometry/optical-numerical-aperture-calculator},
note = {Published July 21, 2026; accessed August 31, 2026}
}RIS
TY - ELEC
AU - MW SysArc
TI - Optical Numerical Aperture Calculator
T2 - MW SysArc Tools
PY - 2026
DA - 2026-07-21
Y2 - 2026-08-31
UR - https://math.mwsysarc.com/trigonometry/optical-numerical-aperture-calculator
N1 - Published July 21, 2026
ER -Clear answers
Frequently asked questions
What does the Optical Numerical Aperture do?
Calculate numerical aperture from refractive index of object space and acceptance half-angle in degrees.
How does the Optical Numerical Aperture work?
The calculator applies c=a sin(b). Optical numerical aperture equals object-space refractive index multiplied by sine of the acceptance half-angle. This page evaluates the relationship directly.
What can I learn from the Optical Numerical Aperture?
It connects the mathematical rule to your chosen numbers and shows each calculation step. Change one input at a time to see how the result responds.
Does MW SysArc receive or store what I enter?
No. The calculation runs locally in your browser. MW SysArc does not receive or store your calculation inputs.
How should I use the result?
Use the steps to understand the method, then verify important school or professional work using the notation and rounding rules required in your setting.
Last reviewed . Calculations tested .