Definitions

• This invention is an optical array converting UN radiation, especially contained in sunlight.
• the spectral characteristic of the transmission of the filter is similar to the sensitivity of human skin to sun burning. That sensitivity is described by the widely recognized Diffey Standard, also called also the Erythema Action Spectrum.
• the devisston Berger UN meter has been widely used over the past two decades to measure UN in good approximation of the Diffey/Erythemal Spectral Response.
• This stationary device is based on a phosphore convertor screen as the principle means to reach a spectral response close to the Erythemal/Diffey Curve.
• US patent 5,196,705 describes a device measuring the intensity and dose of UN.
• the device has an optical array containing: an absorptive filter made of material similar to Schott UG- 11, a photo- luminescentive material and a photodiode.
• the spectral characteristic of the device doesn't match the Diffey Standard.
• the device is too sensitive to UN-A comparing to its sensitivity to UN-B.
• US patent 5,036,311 describes a UN-monitoring system in which a light sensing element is placed under a curved optical element with interference filters imposed on its surface.
• US patent 5,401,970 describes a UN-monitoring device which incorporates a UN-B sensor and a VIS sensor.
• the UN-B detector involved is described to be based on a phosphor convertor screen. Description of the invention
• the invention solves the problem of constructing a device equipped with an optical array converting UN, visible and IR radiation that has the spectral characteristic of the transmission similar to the Diffey Standard. Definition of the relative internal transmission of a set of filters:
• T rel ( ⁇ ) T( ⁇ )/T(310) (2) where: ⁇ wavelength in nano-meters
• D( ⁇ ) (3) The Diffey spectral characteristics will be denoted as D( ⁇ ) (3) where: ⁇ wavelength in nano-meters
• the array contains a system of absorptive filters to block visible and IR radiation, a system of interference filters modifying transmission of UN and/or blocking visible and IR radiation, scattering elements, elements forming the light beam.
• Interference filter/filters is/are made of layers of materials having high and low UN refractive indexes.
• one of the system of interference filters has layers made of Hafnium oxide and/or Zirconium oxide.
• a collimator placed in the optical path forms the light beam.
• the collimator can have surfaces highly absorbing light.
• a scatterer is placed to achieve non-directional characteristic of the array.
• the scatterer can be made of PTFE.
• the array contains the first system of absorptive filters to partly block UN- A, the second system of absorptive filters to block visible and IR radiation and may contain scattering elements and/or system/systems of interference filter/filters.
• the total optical thickness of the first system of absorptive filters is between 0.5 and 10mm.
• a scatterer is placed to achieve non-directional characteristic of the array.
• the scatterer can be made of PTFE.
• additional system/systems of interference filters can be placed to block visible and IR radiation and/or to modify transmission in UN range.
• the internal transmissions are arranged slightly differently.
• the array contains the first system of absorptive filters to partly block UN- A, the second system of absorptive filters to block visible and IR radiation and may contain scattering elements and/or system/systems of interference filter/filters.
• a scatterer is placed to achieve non-directional characteristic of the array.
• the scatterer can be made of PTFE.
• additional system/systems of interference filters can be placed to block visible and LR radiation and/or to modify transmission in UN range.
• This invention allows producing a cheap and simple optical array with a spectral characteristics in the UN-A and UN-B range following the human skin sensitivity described by Diffey Standard.
• the scatterer ensures non-directional characteristics of the array.
• Other standards of skin sensitivity to UN-A and UN-B burning can also be easily followed.
• Fig. 1 presents the construction of the version 1 of the optical array
• Fig. 2 presents the construction of another variant of the invention presented on Fig. 1
• Fig. 3 presents the construction of the version 2 of the optical array
• Fig. 4 presents the construction of the of the version 3 of the optical array.
• Fig. 5 presents T rel ( ⁇ )*D(310)/T reI (310) for optical array from Fig. 2 in comparison with the Diffey Standard D( ⁇ )
• Fig. 6 presents T rel ( ⁇ )*D(310)/T rel (310) for optical array from Fig. 3 in comparison with the Diffey Standard D( ⁇ )
• Fig. 7 presents T r ( ⁇ )*D(310)/T rel (310) for optical array from Fig. 4 in comparison with the Diffey Standard D( ⁇ ).
• Description of the version 1 presents T rel ( ⁇ )*D(310)/T reI (310) for optical array from Fig. 2 in comparison with the Diffey Standard D( ⁇ )
• Fig. 6 presents
• the array contains: the layer 1 that scatters light, a collimator 2 an absorptive filter 3 that makes a system of absorptive filters, a set of interference filters 4 that makes a system of interference filters.
• the absorptive filter 3 is made of material transparent to UV and blocking visible and IR radiation. That property has Ml material, with a characteristics presented in the table below.
• a scatterer I is made of PTFE
• the absorptive filter 3 is a piano -parallel plate, 8mm thick, made of Ml material Schott UG-11 like.
• the set of interference filters 4 that is placed on the absorptive filter's 3 surface consists of 38 layers of Hafnium oxide and or Zirconium oxide and Silica oxide.
• the scatterer I ensures non-directional characteristics of the array.
• the collimator 2 forms the light beam. To achieve desired spectral characteristics the light beam passes through the absorptive filter 3_and the mterference filter 4.
• the array contains: the layer 5 that scatters light, a collimator 6, absorptive filter 7 that makes a system of absorptive filters and a first set of interference filters 8 and a second set of interference filters 9 that both make a system of interference filters.
• the absorptive filter 7 is made of material transparent to UN and blocking visible and IR radiation. That property has Ml material, with a characteristics presented in the table below.
• a scatterer 5 is made of PTFE
• absorptive filter 7 is a piano-parallel plate, 8mm thick, made of Ml material, Schott UG-11 like.
• the first set of interference filters 8 and the second set of interference filters 9 are placed on the absorptive filter's 7 surfaces and together consists of 62 layers of Hafnium oxide and/or Zirconium oxide and Silica oxide.
• the scatterer 5 ensures non-directional characteristics of the array.
• the collimator 6 forms the light beam.
• the light beam passes through the first interference filter 8, the absorptive filter 7 and the second interference filter 9.
• the T re! ( ⁇ )*D(310)/T ⁇ el (310) characteristics of the array is plotted as a broken line
• the Diffey Standard is plotted as a solid line.
• these two curves are close to each other in the 310-325nm range.
• the array contains: the layer 10 that scatters light, a first absorptive filter 11 that makes a first system of absorptive filters, a second absorptive filter VI that makes a second system of absorptive filters.
• the first absorptive filter 11 is made of material transparent to UN with decreasing transmission when the wavelength is changed from 320 to 350nm
• the second absorptive filter V2 is made of material transparent to UN and blocking visible and IR radiation. That property have materials M2 and Ml respectively, with characteristics presented in the table below.
• a scatterer 10 is made of PTFE
• the first absorptive filter 11. is a piano-parallel plate, 1.5mm thick, made of M2 material, Schott GG-19 like
• the second absorptive filter 12 is a piano-parallel plate, 8 mm thick, made of Ml material, Schott UG-11 like.
• the scatterer 10 ensures non-directional characteristics of the array. To achieve desired spectral characteristics the light beam passes through the first absorptive filter 11 and the second absorptive filter 12.
• the array contains: a first absorptive filter 13. that makes a first system of absorptive filters, a second absorptive filter 14 that makes a second system of absorptive filters and a first set of interference filters 15 and a second set of interference filters 16 that both make a system of interference filters.
• the first absorptive filter 3 is made of material transparent to UN with decreasing transmission when wavelength is changed from 320 to 350nm
• the second absorptive filter 14 is made of material transparent to UN and blocking visible and IR radiation. That property have materials M2 and Ml respectively, with characteristics presented in the table below.
• Interference filters are constructed to block visible and IR radiation and or to modify transmission characteristics in UV.
• the first absorptive filter 3 is a piano-parallel plate, 1.5mm thick, made of M2 material, Schott GG-19 like.
• the second absorptive filter 14 with interference filters 15, 16 placed on the filter 14 surfaces are made together by Schott as Schott DUG-11 filter.
• the light beam passes through the first absorptive filter 13, the first interference filter 15, the second absorptive filter 14 and the second interference filter 16.
• T rel mt ( ⁇ ) characteristics of plano-paralel plates made of Ml, M2 with given thickness.
• T rel ⁇ nt ( ⁇ ) The exact values of T rel ⁇ nt ( ⁇ ) are described in the example constructions. These data are example values and it is obvious that the invention is not restricted to them.
• the optical array in the example constructions has the spectral characteristics similar to human skin sensitivity to UV contained in sunhght.
• Fig. 5 presents T rel ( ⁇ )*D(310)/T rel (310) chart for optical array from Fig. 2 in comparison with the Diffey Standard D( ⁇ ),
• Fig. 6 presents
• Fig 4 in comparison with the Diffey Standard D( ⁇ ).
• the biggest discrepancies between the characteristics and the Diffey Standard are for UV-C that is absent in sunlight and UN-A that has a minimal burning power comparing with total burning power of sun UN.

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• 2003
  • 2003-05-21 EP EP03734107A patent/EP1512034A1/de not_active Withdrawn
  • 2003-05-21 CA CA002486807A patent/CA2486807A1/en not_active Abandoned
  • 2003-05-21 AU AU2003239542A patent/AU2003239542A1/en not_active Abandoned

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