Abstract: A method and an apparatus for detecting a filter status. The apparatus is applied to an electronic apparatus, such as a projector, having a ventilation opening and a dust filter, and includes a filter status testing film and a photosensor. The filter status testing film is embedded in the dust filter. The photosensor determines a status of the dust filter by sensing a color variation of the filter status testing film. The method includes sensing the color variation of the dust filter and determining the status of the dust filter according to the color variation.

Abstract: A projector includes a housing including an opening, and a fixture installed on the opening of the housing. A slot is formed on the fixture. The projector further includes a lens-shading ring installed on the fixture in a slidable manner inside the slot, and a lens for projecting images. An end of the lens is installed inside the housing in a slidable manner inside the lens-shading ring.

Abstract: An electronic apparatus includes a key, at least one support, and a circuit board. The key has a first press end, a first contact end, a second press end, and a second contact end. The support is mounted onto the key and between the first contact end and the second contact end. The circuit board has a first contact point corresponding to the first contact end and a second contact point corresponding to the second contact end. When the first press end of the key is pressed down, the first contact end goes down together with the first press end to actuate the first contact point of the circuit board, and the support is against a top surface of the circuit board to prevent the second contact end from actuating the second contact point. Accordingly, the key of the electronic apparatus can function well without any error.

Abstract: A quick disassembly hacksaw includes an inverse U-shaped frame having a flexible triangular front handle on fore end, a rear handle on rear end, a front tube and a rear tube respectively disposed under the fore end and rear end, an adjusting mechanism disposed in the front tube, a positioning rod inserted into the rear tube each of which has a polyhedron for connecting a saw blade and a fastening mechanism comprised of a link and a U-shaped leverage latch pivoted to the positioning rod and a lug under the rear handle and locked by a safety detent on a top of the rear handle. The saw blade is fastened by the fastening mechanism and the tensions thereof is adjusted by the adjusting mechanism.

Abstract: A versatile tubular holder for positioning and operating the hex wrenchs includes a tubular holder having a closed end, an open end, a plurality of circular positioning holes of different diameters spacedly formed in the closed end extending along the length of the lateral walls of the holder, a hollow interior extension projected downward from a middle portion of the holder including a plurality of different sized hexagon inserting holes centrally and spacedly formed in one of the lateral sides extending along the length thereof and an opening abutting a pair of stepped inner wall in the other side opposite to the hexagon inserting holes. It is characterized that a plurality of l-shaped hex wrenchs position their tails into the circular positioning holes respectively when not in use and insert their head into the hexagon inserting holes respectively in operation.