WEARABLE SKIN MONITOR COMPRISING UV SENSOR
[001] The present invention relates to a simple monitor which can be used to assess whether a person has had enough exposure to sunlight.
[002] On sunny days, it can be difficult to tell whether a person has had too much exposure to sunlight before it is too late and they are sunburnt. There are several variables which affect when exposure has become too much, such as humidity, UV exposure, body temperature, age and skin type. Known solutions to this problem are generally complex devices which are not suitable for use by the general public.
[003] A way of ameliorating these problems has been sought. [004] According to the invention there is provided a wearable standalone skin monitor for use with a person or animal which skin monitor consists essentially of:
one or more sensors suitable for measuring a skin property which include a UV sensor;
one or more indicators;
one or more switches which include a power switch for switching the Skin monitor on or off; an electrical power supply; and
a programmable logic circuit includes a processor and a programmable electronic memory; wherein the logic circuit is operably connected to the sensors, indicators, switches and power supply; wherein the logic circuit is programmed with one or more predetermined values to characterise the type of person or animal which is using the monitor;
wherein the programmable electronic memory is programmed with a predetermined value for a safe accumulated UV exposure level for the predetermined type of person or animal;
wherein the logic circuit is programmed to operate a warning indicator when a measured accumulated
UV exposure level exceeds the predetermined safe value.
[005] Advantages of the skin monitor according to the invention include that it is straightforward to use by the public as it uses predetermined values to characterise the type of person or animal which is using the device and so it avoids a lot of confusion and complication. Furthermore, the skin monitor is standalone and does not require any separate device such as a smartphone to check whether a UV exposure level is safe. As an example, this makes life much easier for a mother who can simply look at the monitor which their baby or child is wearing to determine whether their exposure to sunlight has lasted too long.
[006] In some embodiments, the skin monitor may include a non-essential feature which is not related to measuring a skin property such as a strap. In some embodiments, the wearable standalone skin monitor for use with a person or animal may consists of:
an optional strap;
one or more sensors which include a UV sensor;
one or more indicators;
one or more switches which include a power switch for switching the Skin monitor on or off; an electrical power supply; and
a programmable logic circuit includes a processor and a programmable electronic memory; wherein the logic circuit is operably connected to the sensors, indicators, switches and power supply; wherein the logic circuit is programmed with one or more predetermined values to characterise the type of person or animal which is using the monitor;
wherein the programmable electronic memory is programmed with a predetermined value for a safe accumulated UV exposure level for the predetermined type of person or animal;
wherein the logic circuit is programmed to operate a warning indicator when a measured accumulated UV exposure level exceeds the predetermined safe value.
[007] In some embodiments, the skin monitor calculates the measured accumulated UV exposure level at predetermined time intervals by the following steps:
sensing a UV level using the UV sensor;
calculating an accumulated UV exposure level by adding the sensed UV level to a saved UV exposure level; and
saving the calculated accumulated UV exposure level with an associated number of time intervals to provide a measured accumulated UV exposure level. In some embodiments, a measured accumulated UV exposure level may include measured accumulated UV exposure level statistical value such as a mean measured accumulated UV exposure level value, a measured accumulated UV exposure level range value, and/or a measured accumulated UV exposure level standard deviation value. In some embodiments, a predetermined time interval may be from 1 second to 5 minutes, for example the predetermined time interval may be: 1, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55 seconds or 1, 2, 3, 4 or 5 minutes. [008] In some embodiments, the skin monitor may have a strap for attaching the skin monitor to a part of a human or animal body. In some embodiments, the strap may have two arms which may be secured together using a buckle or respective hook and loop patches. In some embodiments, the strap may be elasticated.
[009] In some embodiments, the programmable logic circuit may have a programmable non-volatile memory, a read/write volatile memory and a processor.
[0010] In some embodiments, the one or more sensors may additionally include a humidity sensor and/or a temperature sensor (for example a skin temperature sensor). In some embodiments, the one or more sensors may include a skin temperature sensor provided on a skin contacting surface of the Skin monitor.
[0011] In some embodiments, the one or more indicators may include a lamp for a signal to indicate whether the Skin monitor is switched on, a first indicator for providing a warning signal and/or a second indicator for providing an alert signal. In some embodiments, the one or more indicators may provide two or more types of signal, for example a constant signal or a flashing signal which may be characterised by different flashing speeds.
[0012] In some embodiments, the one or more switches may include a user-type switch for programming the logic circuit with a predetermined value to characterise the type of person or animal which is using the monitor. In some embodiments, the or each of the one or more switches may be a slidable or rotatable switch. In some embodiments, a rotatable switch may have a slot which receives a screwdriver blade such that it can be rotated.
[0013] In some embodiments, the programmable memory is programmed with a predetermined marginal value which indicates a degree of harm and the logic circuit is programmed to operate a warning indicator when a measured accumulated UV exposure level differs from the predetermined safe value by the predetermined marginal value.
[0014] In some embodiments, the electrical power supply may include a solar power generator, a battery and/or a connector to an electrical power socket. In some embodiments, the electrical power supply may comprise a battery provided in a battery compartment.
[0015] In some embodiments, the skin monitor may include a skin temperature sensor, the programmable electronic memory may be programmed with a predetermined value for a safe skin temperature for the predetermined type of person or animal, and the logic circuit may be programmed to operate a warning indicator when a measured skin temperature exceeds the predetermined safe value. In some embodiments, at predetermined time intervals the logic circuit may be programmed to take measurements of the skin temperature and to compare the skin temperature measurement with the programmed value for a safe skin temperature, and to operate a warning indicator when the measured skin temperature exceeds the programmed safe value by a
predetermined marginal value for the appropriate predetermined person or animal type. In some embodiments, a person or animal may be characterised by skin type and/or age group.
[0016] In some embodiments, the skin monitor may include a temperature sensor and a humidity sensor, the programmable electronic memory may be programmed with a predetermined value for a safe heatstroke risk for the predetermined type of person or animal, and the logic circuit may be programmed to operate a warning indicator when a calculated heatstroke risk exceeds the predetermined safe value. There are many different known ways to calculate heatstroke risk. In some embodiments, the logic circuit may be programmed to calculate heatstroke risk as a function of accumulated UV exposure, temperature, and humidity. A skilled person would know a suitable function to use.
[0017] In some embodiments, at predetermined intervals the logic circuit may be programmed to calculate a measured accumulated heatstroke risk by the following steps:
sensing a UV level using the UV sensor, a temperature using the temperature sensor and the humidity using the humidity sensor;
calculating a heatstroke risk using a heatstroke risk function; and
saving the calculated heatstroke risk with an associated number of time intervals to provide a measured accumulated heatstroke risk. In some embodiments, a measured accumulated heatstroke risk may include measured accumulated heatstroke risk statistical value such as a mean measured accumulated heatstroke risk value, a measured accumulated heatstroke risk range value, and/or a measured accumulated heatstroke risk standard deviation value.
[0018] The invention will now be illustrated with reference to the following Figures of the accompanying drawings which are not intended to limit the scope of the claimed invention:
FIGURE 1 shows a schematic plan view of an upper surface of a first embodiment of a skin monitor according to the invention; and FIGURE 2 shows a schematic plan view of a lower surface of a first embodiment of a skin monitor according to the invention.
[0019] The first embodiment of the skin monitor according to the invention is indicated generally at 10 on Figures 1 and 2. Skin monitor 10 has a housing 20 and a strap 50. Housing 20 has an upper display surface 30 and a lower skin-contacting surface 40.
[0020] Strap 50 has first and second arms 52, 54. Each arm 52, 54 of strap 50 is formed from an elasticated material and has a respective hook and loop patch 53, 55 mounted on it such that the strap 50 may be wrapped around a person's limb and secured using the hook and loop patches. First arm 52 has a hook or loop patch 53 mounted on its upper surface and second arm 54 has a hook or loop patch 55 mounted on its lower surface.
[0021] Housing 20 contains a programmable logic circuit (not shown). The programmable logic circuit has a programmable non-volatile electronic memory, a read/write volatile electronic memory which loses its saved data when the skin monitor is switched off, and a processor. On the upper surface 30 of housing 20, there are a UV sensor 34, a humidity sensor 35, a LED lamp 32 to indicate when the Skin monitor is switched on, a first indicator 36 and a second indicator 38, which are each operably connected to the processor of the logic circuit. First indicator 36 is adapted to provide one or more types of amber warning signal and second indicator 38 is adapted to provide one or more types red alert signal. The different types of warning signal may be characterised by being constant or by being flashing warning signals for example a flashing signal having a different flashing speed. The LED lamp 32 is further configured to indicate when the battery is running low such as by flashing when the skin monitor is switched on.
[0022] On the lower skin-contacting surface 40 of housing 20, there are a skin temperature sensor 48, rotatable user-type switches 41,43, a slidable power switch 44 arranged to slide in a slot 45 and a battery compartment 46, which are each operably connected to the processor of the logic circuit. Rotatable user-type switches 41,43 each have a slot 42 which is arranged to receive a screwdriver blade such that they can be rotated between individual positions such that each rotatable user-type switch 41,43 may be used to program options for two different settings. For example, rotatable user- type switch 41 may be used to program a pre-set skin type such as a sensitive, fair or normal skin type and rotatable user-type switch 43 may be used to program a pre-set age group such as infant, child or adult. Second switch 45 is arranged to slide within slot 44 between two positions such that the Skin monitor 10 may be switched on or off.
[0023] In an alternative embodiment, a slidable user-type switch may be used instead of rotatable user-type switch 41,43. In an alternative embodiment, the logic circuit may be programmed with one or more predetermined values to characterise the type of person or animal which is using the monitor such that the Skin monitor 10 does not have the rotatable user-type switches 41,43. In an alternative embodiment, the slidable power switch 44 may be replaced by a rotatable power switch.
[0024] The programmable non-volatile memory comprises a database having safe values for: skin temperature, statistics related to accumulated UV exposure, and heat stroke risk for each different skin types and for each different age group. The values for skin temperature, accumulated UV exposure and heat stroke risk may include marginal values by which the safe values may be exceeded which marginal values indicate a low risk of harm, a moderate risk of harm and a high risk of harm.
[0025] When the power switch 45 is slid within slot 44 to the on position, at predetermined time intervals the logic circuit is programmed to take measurements of the skin temperature using sensor 48, to save the measured skin temperature in the read/write memory and to compare the measured skin temperature with the safe temperature value in the database for the appropriate pre-set type of person or animal for example skin type and/or age group. When the measured skin temperature exceeds the safe temperature by a first predetermined marginal value indicating a moderate risk of harm, the processor is programmed to operate the first indicator 36 to give a first type of warning signal for a pre-determined period. Where the measured temperature exceeds the safe temperature by a second predetermined marginal value indicating a high risk of harm or has exceeded the safe temperature by a first predetermined temperature difference indicating a moderate risk of harm for a predetermined period, the processor is programmed to operate the second indicator 38 to give a first type of warning signal for a pre-determined period.
[0026] When the power switch 45 is slid within slot 44 to the on position, the logic circuit is programmed to take measurements of the UV level using sensor 34 at predetermined time intervals, to save an accumulated UV exposure level in the read/write memory, and at predetermined time intervals to compare the accumulated UV exposure level with the UV exposure levels in the database for the appropriate pre-set skin type and/or age group. Where the accumulated UV exposure level is within the range of values having a moderate risk of harm, the processor is programmed to operate the first indicator 36 to give a second type of warning signal for a pre-determined period. Where the accumulated UV exposure level is within the range of values having a high risk of harm or has been within the range of value having a moderate risk of harm for a predetermined period, the processor is programmed to operate the second indicator 38 to give a second type of warning signal for a predetermined period.
[0027] When the power switch 45 is slid within slot 44 to the on position, the logic circuit is programmed to take measurements of the UV level using sensor 34 and humidity using sensor 35 at predetermined time intervals to calculate a heatstroke risk using a heatstroke risk function, to save the calculated heatstroke risk or an accumulated heatstroke risk in the read/write memory, and at predetermined time intervals to compare the saved heatstroke risk with the heat stroke risk levels in
the database for the appropriate pre-set skin type and/or age group. Where the heatstroke risk level is within the range of values having a moderate risk of harm, the processor is programmed to operate the first indicator 36 to give a third type of warning signal for a pre-determined period. Where the heatstroke risk level is within the range of values having a high risk of harm or has been within the range of value having a moderate risk of harm for a predetermined period, the processor is programmed to operate the second indicator 38 to give a third type of warning signal for a predetermined period.