Abstract: A sun monitoring device has a sensing sheet mounted in a housing to receive incident sunlight through a UV pass filter. The sheet contains a dye which luminesces in response to the incident light in a wavelength range within the UV range, and emits light within the sheet at longer wavelengths. The emitted light is internally reflected in the sheet and emerges at the edge of the sheet. A sensor is disposed to receive such light emerging from a portion of the sheet edge and generate signals in response thereto. Computing means is coupled to the sensor to determine from these signals the power of incident UV light on the sensing sheet in the selected wavelength range.

Abstract: An electronic game apparatus for determining the presence and optionally the identity of playing pieces. Each playing piece (10) is provided with a resonator circuit (12,14,16), which may be tuned so that each playing piece or type or piece has a unique resonant frequency. A board (2) defining a number of particular playing positions is provided with transmit and receive coils (4,6) underneath it to stimulate the resonator circuit of a piece and to sense the resonant signal respectively. An amplifier is provided between the two sets of coils to amplify the signal generated by the resonant circuit. A resonant signal results if a playing piece is placed on a particular position on the board (2). The frequency of this signal is detected and may then be determined and the piece thereby identified.

Abstract: Electronic game apparatus comprising a board displaying discrete playing areas and a number of playing pieces. Transmit and receive coils are provided beneath the surface of the board, preferably at right angles to each other, and each playing piece is provided in its base with an element. Means are provided for supplying a high-frequency current to each transmit coil in turn and for detecting the voltage induced in the receive coils for each discrete playing area. The presence of a playing piece on the playing area being tested, will affect the voltage induced in the receive coils and hence the presence, absence or type if desired, of a playing piece may be determined. The element preferably consists of any suitable metal or ferromagnetic material. Playing pieces of different types may be provided with elements of different materials.

Abstract: A sensory electronic game which includes a board having a number of defined positions each provided with an isotropic field sensor such as a reed switch which has open and closed positions depending upon the presence or absence of a magnetic field, and two sets of playing pieces. All pieces have a magnet with its N-S axis substantially upright to provide a magnetic field which will open or close the sensor when a piece is positioned on the associated board position. To avoid a lack of detection if one piece is quickly replaced by another piece, the pieces of one set have the N pole facing downwardly whilst the pieces of the other set have the S pole facing downwardly. Then, by detecting the opening and closing of the sensors including momentary open and closed positions during capture or replacement of a piece of one set by a piece of another set, movement of pieces can be determined.