Optics & Vision Lab
Analyze lens focal lengths, convert clinical visual acuity fractions, compute prism deviations, simulate color temperatures, and evaluate light bulb efficacy.
Visual Acuity Converter
Translate visual acuity measurements across standard Snellen feet (20/20), Snellen meters (6/6), decimal fraction, LogMAR, and visual efficiency percentages.
Acuity Measurement Standards
Snellen (US) uses feet as reference distance (20 feet). Metric scales directly to meters (6 meters). LogMAR is logarithmic minimum angle of resolution, commonly used in advanced clinical research studies.
Normal / Standard Vision
The reference standard for normal human vision resolution.
Explore Additional Utilities
Tidal Rule of Twelfths Calculator
Estimate hourly tide heights and flow volumes between high and low tide periods using the standard maritime rule.
Cable run — signal type + length → gauge required
Compute copper loop line resistance, voltage drop, and power loss to recommend the optimal wire gauge size (AWG).
Irrigation Flow & Volume Sizer
Convert water flow rates, and calculate irrigation water depths and volumes over target agricultural land.
Fabric & Thread Density Calibrator
Analyze fabric weights, compare cotton single-ply thread counts, and calculate textile density.
Encoder resolution (PPR ↔ degrees per pulse)
Convert between encoder Pulses Per Revolution (PPR), Cycles Per Revolution (CPR), and angular resolution down to arcseconds.
Net metering — units exported ↔ bill credit estimate
Estimate utility bill credits, net energy offsets, and financial yields under 1:1 net metering or dual-rate net billing programs.
Drilling rate — ROP in m/hr ↔ ft/hr
Translate Rate of Penetration (ROP) and calculate specific drilling time, drilling speed efficiency, and shift performance.
Clay shrinkage — wet size ↔ fired size
Calculate wet, bone-dry, and kiln-fired pottery dimensions and analyze total contraction rates.
Yeast pitch rate — batch volume + gravity → grams of yeast
Determine required yeast cell counts and dry yeast weight based on batch volume, wort gravity, and target pitch rates.
pH adjustment — acid/alkali drops ↔ pH change estimate
Estimate acidifying or alkalizing solution amounts to safely adjust formulation pH values.
Propeller pitch ↔ boat speed — theoretical boat speed
Calculate theoretical boat speed and actual speed based on propeller pitch, engine RPM, gear ratio, and hull slip percentages.
Arrow spine ↔ draw weight + length — stiffness matching
Estimate required arrow static spine rating (stiffness) based on bow draw weight, arrow length, and bow type.
Ocean depth ↔ pressure — bar per 10 meters rule
Calculate hydrostatic and total pressure in the ocean based on depth, water density, and gravity constants.
Twist rate — caliber ↔ bullet length → stabilization
Calculate the optimal barrel rifling twist rate needed to stabilize a bullet of a given length, caliber, and velocity.
CMYK ↔ Pantone Matcher
Approximate CMYK values to the closest solid Pantone matching system (PMS) color swatch.
Canopy cover percentage ↔ light transmission
Convert forest canopy coverage percentages to photosynthetically active light transmittance and estimate Leaf Area Index (LAI).
Barometric Altimeter Settings
Calibrate pressure settings between QNH and QFE based on airfield elevation and temperature.
Crease pattern scale — diagram size ↔ actual paper needed
Scale geometric origami crease patterns and tessellations to starting square sheet sizes.
Lactate threshold — heart rate % ↔ training zone
Convert heart rate threshold percentages into targeted cardiovascular athletic training zones.
Batting average ↔ on base percentage — baseball stats
Convert batting average, walks, and plate appearances into On-Base Percentage (OBP).