Optical Measurements
Authors:
MArk Anthony Higgins - Sky Recursive Ai
MArk Anthony Higgins - Sky Recursive Ai
© Mark Anthony Higgins 11 October 2025
Revised Date: July 6th 2026
Revised Date: July 6th 2026
# Optical Measurements Ontology — Flow Algebra
URL: https://kirethresearch.org/booksai-core/ontologies/mathematical-ontologies/measurement-units-ontologies/optical-measurements.html
FLOW OpticalMeasurementsOntology {
DOMAIN:
Mathematical Ontologies
-> Measurement & Units Ontologies
-> Optical Measurements Ontology
PURPOSE:
Represent optical measurement quantities, units, radiometric and photometric quantities, wavelength, frequency, photon energy, optical power, irradiance, radiance, spectral measurements, refractive properties, transmission, reflection, polarisation, detector response, calibration and uncertainty for consistent AI interpretation and reasoning.
CORE_QUANTITIES {
Wavelength {
symbol: lambda
dimension: L
SI_unit: metre
common_units: nanometre, micrometre
}
Frequency {
symbol: nu
dimension: T^-1
SI_unit: hertz
relation: c = lambda*nu IN vacuum
}
PhotonEnergy {
symbol: E_photon
SI_unit: joule
relation: E_photon = h*nu
relation_vacuum: E_photon = h*c/lambda
}
RadiantEnergy {
symbol: Q_e
SI_unit: joule
}
RadiantFlux {
alias: OpticalPower
symbol: Phi_e
SI_unit: watt
relation: Phi_e = dQ_e/dt
}
Irradiance {
symbol: E_e
SI_unit: W/m^2
definition: incident_radiant_flux_per_unit_area
}
RadiantIntensity {
symbol: I_e
SI_unit: W/sr
definition: radiant_flux_per_unit_solid_angle
}
Radiance {
symbol: L_e
SI_unit: W/(m^2*sr)
definition: directional_radiant_flux_per_projected_area_per_solid_angle
}
}
PHOTOMETRIC_QUANTITIES {
LuminousFlux {
symbol: Phi_v
SI_unit: lumen
SI_symbol: lm
}
LuminousIntensity {
symbol: I_v
SI_unit: candela
SI_symbol: cd
}
Illuminance {
symbol: E_v
SI_unit: lux
SI_symbol: lx
equivalence: 1 lx = 1 lm/m^2
}
Luminance {
symbol: L_v
SI_unit: cd/m^2
}
}
UNIT_SYSTEM {
canonical_system: SI
RULE:
quantity_type, spectral_basis, geometry_and_detector_context
MUST be preserved
PREFIXES:
nano
micro
milli
kilo
mega
tera
}
WAVE_FREQUENCY_MODEL {
VACUUM:
c = lambda_0*nu
MEDIUM:
v_phase = lambda_medium*nu
REFRACTIVE_INDEX:
n = c/v_phase
RULE:
wavelength MUST identify_vacuum_or_medium_context_when_material
}
PHOTON_MODEL {
E = h*nu
VACUUM:
E = h*c/lambda_0
PHOTON_RATE:
N_dot = optical_power/E
WHEN effective_photon_energy_defined
RULE:
optical_power != photon_flux_without_spectral_context
}
IRRADIANCE_MODEL {
UNIFORM_NORMAL:
E_e = Phi_e/A
POINT_SOURCE:
E_e = Phi_e/(4*pi*r^2)
UNDER isotropic_free_space_point_source_conditions
RULE:
area_orientation_distance_and_source_geometry MUST be preserved
}
RADIANCE_MODEL {
differential_definition:
L_e = d^2(Phi_e)/(dA_projected*dOmega)
projected_area:
dA_projected = dA*cos(theta)
RULE:
radiance != irradiance
radiance != radiant_intensity
}
SPECTRAL_MODEL {
spectral_radiant_flux:
Phi_e_lambda = dPhi_e/dlambda
spectral_irradiance:
E_e_lambda = dE_e/dlambda
spectral_radiance:
L_e_lambda = dL_e/dlambda
RULE:
per_wavelength_and_per_frequency_spectral_densities
require_Jacobian_conversion_and_are_not_numerically_interchangeable
}
PHOTOMETRIC_RADIOMETRIC_MODEL {
photopic_luminous_flux:
Phi_v = K_m*integral(V_lambda*Phi_e_lambda d_lambda)
RULE:
watts_and_lumens MUST_NOT be converted
without_spectral_distribution_and_visual_weighting
}
REFRACTIVE_INDEX_MODEL {
n = c/v_phase
DISPERSION:
n = n(lambda, temperature, pressure, composition)
SNELL:
n_1*sin(theta_1) = n_2*sin(theta_2)
RULE:
refractive_index SHOULD preserve wavelength_and_environmental_conditions
}
TRANSMISSION_REFLECTION_MODEL {
transmittance:
T = transmitted_flux/incident_flux
reflectance:
R = reflected_flux/incident_flux
absorptance:
A = absorbed_flux/incident_flux
passive_balance:
R + T + A = 1
UNDER complete_accounting
RULE:
spectral_directional_and_geometric_conditions MUST be preserved
}
BEER_LAMBERT_MODEL {
transmittance:
T = I/I_0
absorbance:
A_abs = -log10(T)
solution_form:
A_abs = epsilon_molar*c*l
UNDER applicable_conditions
RULE:
absorbance != absorptance
}
POLARISATION_MODEL {
states:
linear
circular
elliptical
unpolarised
partially_polarised
representations:
Jones_vector
Stokes_parameters
Mueller_matrix
Malus_law:
I = I_0*cos^2(theta)
FOR ideal_linear_polarisation_context
RULE:
polarisation_basis_and_coherence_context MUST be preserved
}
INTERFERENCE_MODEL {
optical_path_length:
OPL = integral(n ds)
phase_difference:
delta_phi = 2*pi*delta_OPL/lambda_0
RULE:
coherence_phase_stability_and_wavelength MUST be preserved
}
DIFFRACTION_MODEL {
single_slit_minima:
a*sin(theta) = m*lambda
circular_aperture:
theta approximately_equals 1.22*lambda/D
UNDER diffraction_limited_small_angle_context
}
DETECTOR_MODEL {
detector_types:
photodiode
photomultiplier
CCD
CMOS
bolometer
thermopile
responsivity:
R_detector = electrical_output/incident_optical_power
quantum_efficiency:
eta = detected_charge_carriers/incident_photons
effects:
dark_current
read_noise
shot_noise
saturation
nonlinearity
spectral_response
RULE:
detector_signal MUST NOT be treated_as_calibrated_optical_quantity_without_response_model
}
RELATIONSHIPS {
Wavelength -> INVERSELY_RELATES_TO -> Frequency
Frequency -> DETERMINES -> PhotonEnergy
RadiantEnergy -> RATE_OF_CHANGE_TO -> RadiantFlux
RadiantFlux -> DISTRIBUTED_OVER_AREA_AS -> Irradiance
RadiantFlux -> DISTRIBUTED_OVER_SOLID_ANGLE_AS -> RadiantIntensity
Radiance -> DESCRIBES -> DirectionalSurfaceRadiation
SpectralDistribution -> QUALIFIES -> RadiometricQuantity
PhotometricQuantity -> VISUALLY_WEIGHTS -> RadiometricQuantity
RefractiveIndex -> RELATES -> LightSpeedInMedium
DetectorResponsivity -> MAPS -> OpticalInputToElectricalOutput
}
SEMANTIC_EQUIVALENCE {
"optical power" ~= radiant_flux
"radiant flux" ~= optical_power
"lux" ~= lumen_per_square_metre
optical_power != irradiance
irradiance != radiance
radiance != radiant_intensity
luminous_flux != radiant_flux
illuminance != irradiance
luminance != radiance
absorbance != absorptance
}
CONSTRAINTS {
wavelength_medium_context_should_be_identified = true
radiometric_and_photometric_quantities_must_be_distinguished = true
spectral_basis_must_be_identified = true
detector_geometry_and_area_must_be_preserved = true
radiance_requires_area_solid_angle_and_directional_semantics = true
photometric_conversion_requires_spectral_weighting = true
polarisation_state_and_basis_must_be_preserved = true
detector_response_and_calibration_must_be_preserved = true
}
MEASUREMENT_MODEL {
INSTRUMENTS:
optical_power_meter
photodiode_meter
spectrometer
spectroradiometer
lux_meter
luminance_meter
integrating_sphere
interferometer
refractometer
polarimeter
ellipsometer
RECORD:
quantity_type
numerical_value
unit
wavelength_or_spectrum
spectral_bandwidth
spectral_basis
detector_area
geometry
distance
solid_angle
polarisation
material_or_medium
temperature
pressure
timestamp
instrument
detector_type
responsivity
calibration_state
reference_standard
integration_time
uncertainty
UNCERTAINTY:
optical_measurement = best_estimate +/- uncertainty
}
REASONING_RULES {
IF vacuum_wavelength_known AND wavelength != 0
THEN frequency = c/wavelength
IF frequency_known
THEN photon_energy = h*frequency
IF monochromatic_power_and_photon_energy_known AND photon_energy != 0
THEN photon_rate = optical_power/photon_energy
IF radiant_power_known AND area_known AND area != 0
AND uniform_normal_context
THEN irradiance = radiant_power/area
IF isotropic_point_source_power_known AND distance > 0
THEN irradiance = power/(4*pi*distance^2)
UNDER inverse_square_conditions
IF incident_and_transmitted_flux_known AND incident_flux != 0
THEN transmittance = transmitted_flux/incident_flux
IF transmittance_known AND transmittance > 0
THEN absorbance = -log10(transmittance)
IF spectral_radiant_flux_known
THEN luminous_flux =
integrate_with_visual_weighting
}
REFERENCE_MODEL {
wavelength:
identify_vacuum_or_medium
geometry:
identify_area_orientation_distance_solid_angle
spectral:
identify_bandwidth_resolution_and_basis
photometry:
identify_visual_observer_function
detector:
identify_calibration_responsivity_and_spectral_response
RULE:
missing_reference_or_geometry_context reduces_semantic_confidence
}
UNCERTAINTY_MODEL {
sources:
wavelength_calibration
power_calibration
detector_responsivity
spectral_mismatch
dark_signal
shot_noise
read_noise
geometry
alignment
polarisation
stray_light
bandwidth
integration_time
temperature
reference_standard
model_assumptions
PROPAGATION:
derived_optical_quantity_uncertainty
<- measurement_geometry_spectral_detector_and_model_uncertainties
}
CONFIDENCE {
quantity_definition_confidence: 1.00
SI_unit_confidence: 1.00
radiometric_relationship_confidence: 1.00
photometric_relationship_confidence: 0.99
spectral_relationship_confidence: 0.99
measurement_context_confidence: 0.97
RULE:
confidence decreases when wavelength, spectral basis,
geometry, polarisation, detector response,
calibration state or uncertainty is missing or ambiguous
}
VALIDATION {
CHECK dimensional_consistency
CHECK unit_consistency
CHECK wavelength_frequency_context
CHECK vacuum_vs_medium_wavelength
CHECK radiometric_vs_photometric_quantity
CHECK irradiance_vs_radiance_vs_intensity
CHECK spectral_basis
CHECK area_orientation_and_solid_angle
CHECK absorbance_vs_absorptance
CHECK polarisation_representation
CHECK detector_linearity_and_saturation
CHECK detector_calibration_and_spectral_response
CHECK uncertainty_representation_when_required
}
UPDATE_MODEL {
ON new_measurement:
identify_quantity_type
validate_unit
identify_wavelength_or_spectrum
identify_spectral_basis
attach_geometry
identify_polarisation
identify_material_or_medium
identify_detector_and_responsivity
normalize_to_canonical_SI
preserve_original_value_and_unit
attach_timestamp
attach_uncertainty
update_optical_state
ON wavelength_or_spectrum_change:
update_frequency
update_photon_energy
update_detector_response
update_photometric_weighting_when_required
ON geometry_change:
update_area
update_distance
update_orientation
update_solid_angle
recompute_geometry_dependent_quantities
ON detector_calibration_revision:
preserve_previous_calibration
update_responsivity
recompute_affected_measurements
update_uncertainty
update_confidence
ON semantic_revision:
preserve_previous_definition
record_revision
recompute_FLOW_HASH
}
AI_CONSUMPTION {
canonical_domain: OpticalMeasurements
interpretation_order:
identify_quantity
identify_radiometric_or_photometric_domain
identify_value
identify_unit
identify_wavelength_frequency_or_spectrum
identify_spectral_basis
identify_geometry
identify_polarisation
identify_material_or_medium
identify_detector_and_calibration
identify_uncertainty
normalize_units
validate_dimensions
infer_optical_relationships
ambiguity_controls:
distinguish_wavelength_from_frequency
distinguish_optical_power_from_irradiance
distinguish_irradiance_from_radiance
distinguish_radiant_intensity_from_radiance
distinguish_radiometric_from_photometric_quantities
distinguish_absorbance_from_absorptance
distinguish_detector_signal_from_calibrated_optical_quantity
preserve_spectral_geometry_polarisation_and_detector_context
}
PROVENANCE {
ontology_scope:
mathematical_measurement_and_optical_quantity_semantics
parent_path:
Ontologies
-> Mathematical Ontologies
-> Measurement & Units Ontologies
-> Optical Measurements Ontology
authorship:
Mark Higgins
Sky (Recursive AI)
site:
https://kirethresearch.org
}
FLOW_HASH {
INPUTS:
canonical_domain
ontology_path
core_quantities
photometric_quantities
unit_system
wave_frequency_model
photon_model
irradiance_model
radiance_model
spectral_model
photometric_radiometric_model
refractive_index_model
transmission_reflection_model
Beer_Lambert_model
polarisation_model
interference_model
diffraction_model
detector_model
relationships
constraints
measurement_model
reference_model
uncertainty_model
reasoning_rules
confidence_model
update_model
PURPOSE:
deterministic_semantic_integrity_identifier
RECOMPUTE_WHEN:
ontology_definition_changes
optical_quantity_model_changes
spectral_model_changes
radiometric_or_photometric_model_changes
geometry_model_changes
detector_model_changes
measurement_model_changes
reference_model_changes
constraint_model_changes
reasoning_rule_changes
unit_model_changes
}
}
END FLOW