Abstract: A method and apparatus for transmitting light through a light absorbing medium in which a light transmissive fluid column or channel contiguous with the light absorbing medium is formed in the light absorbing medium. The light is introduced into a light inlet end of the column of light transmissive fluid, whereby the light is transmitted in the column of light transmissive fluid through the light absorbing medium until exiting a light outlet end of the column. The invention has applicability to the field of fiber optics and downhole applications of lasers, such as for wellbore drilling and completion activities.

Abstract: Methods, systems, and devices related to downhole wellbore operations such as drilling and completing wells in an earth formation that include a laser device. The method includes lasing a rock and detecting an optical response of the lased rock. It can be determined from the optical response whether the lased rock is responding as specified (e.g. spalling, melting, etc.) If the lased rock is not responding as specified, one or more laser parameters are adjusted to achieve the specified response. Spalling is determined by the detection of sparks, or other light that erratically changes in intensity over time, by an optical detector. The detection of steady light may indicate other types of rock removal mechanisms, such as melt or dissociation.

Abstract: A method and apparatus for transmitting light through a light absorbing medium in which a light transmissive fluid column or channel contiguous with the light absorbing medium is formed in the light absorbing medium. The light is introduced into a light inlet end of the column of light transmissive fluid, whereby the light is transmitted in the column of light transmissive fluid through the light absorbing medium until exiting a light outlet end of the column. The invention has applicability to the field of fiber optics and downhole applications of lasers, such as for wellbore drilling and completion activities.

Abstract: A construction saw blade having pluralities of cutting teeth along upper and lower edge surfaces thereof, an aperture transversely extending through the blade adjacent its rearwardly facing back end of a configuration and dimension to receive a fastener to removably secure the blade to a reciprocating saw for use, and wherein each plurality of cutting teeth include rake angles for cutting substantially only on a pull stroke of the reciprocating saw.

Abstract: The present invention provides for a method of improving the pull-up characteristic of a leather substrate darkened with a finishing oil modified by dissolving a modifier in a conventional finishing oil. The modifier may be polymerized from a monomer mix of alkyl acrylates and alkyl methacrylates. Improved pull-up characteristic of a leather substrate is esthetically very appealing and is highly desired by a consumer. The modifier of the present invention increases the viscosity of the finishing oil, thereby extending the open time, which is a time duration during which the oil applied over the leather substrate surface stays on the surface. Increased open time permits a manufacturer to spread the oil over more area of the leather substrate than conventional unmodified finishing oils, without substantially affecting the pull-up characteristic of a leather substrate darkened with the finishing oil.