Abstract: An apparatus is provided. The apparatus includes a laser generation device configured to emit a laser signal to a semiconductor fabrication component. The apparatus includes a reflection detection device configured to receive a reflection signal comprising light, of the laser signal, reflected by a surface of the semiconductor fabrication component. The reflection detection device includes an optical filter. The optical filter is configured to block light, of the reflection signal, that has a wavelength outside a defined range of wavelengths. The optical filter is configured to provide filtered light, from the reflection signal, that has a wavelength within the defined range of wavelengths. The reflection detection device includes a light sensor configured to generate an electrical signal based upon the filtered light. The apparatus includes a computer configured to determine, based upon the electrical signal, measures of electrostatic field strength at the surface of the semiconductor fabrication component.

Abstract: A bypass-type motor protecting device includes: a casing fitted into a bypass opening in a body housing of a vacuum cleaner and having an inner abutment wall; a seat body having a bypass entry port; a valve body unit movable within the casing relative to the bypass entry port and including a valve disc to be engaged with and disengaged from the seat body, a plunger body having an externally accessible operated head and an axially extending threaded shank, and an abutment member threadedly engaged with the shank such that rotation of the operated head results in a change of an axial distance between the abutment member and the inner abutment wall; and a biasing member disposed to bias the abutment member and the inner abutment wall such that a biasing force thereof is varied in strength by the change of the axial distance.

Abstract: A bypass-type motor protecting device includes: a casing fitted into a bypass opening in a body housing of a vacuum cleaner and having an inner abutment wall; a seat body having a bypass entry port; a valve body unit movable within the casing relative to the bypass entry port and including a valve disc to be engaged with and disengaged from the seat body, a plunger body having an externally accessible operated head and an axially extending threaded shank, and an abutment member threadedly engaged with the shank such that rotation of the operated head results in a change of an axial distance between the abutment member and the inner abutment wall; and a biasing member disposed to bias the abutment member and the inner abutment wall such that a biasing force thereof is varied in strength by the change of the axial distance.