Abstract: An optical information storage medium comprising a transparent substrate and an information carrying layer positioned on one side of the substrate, wherein the information carrying layer contains at least 30 percent by volume of tin and at least 20 percent by volume of nickel oxide. The information carrying layer may be formed directly on one surface of the substrate. Alternatively, the information storage medium may further comprise a first spacer layer formed on one surface of the substrate and a second spacer layer which intervenes between the first spacer layer and the information carrying layer, wherein the first spacer layer is substantially transparent to a radiation with a predetermined wavelength and is larger in refractive index than the substrate at the aforesaid wavelength and the second spacer layer is substantially transparent to the aforesaid radiation and is smaller in refractive index than the first spacer layer at the aforesaid wavelength.

Abstract: An optical recording medium is disclosed which allows information to be recorded thereinto and read thereoutof by means of semiconductor laser light. The recording medium comprises at least a substrate and a recording layer formed on one or both sides of the substrate. Information is recorded into and read from the recording layer by laser light. The recording layer comprises an organic film of a naphthoquinonoid dye corresponding to the following molecular formula or an organic film whose major component is the naphthoquinonoid dye: ##STR1## where R is a first auxochrome and R' a second auxochrome. The first auxochrome is a hydroxyl group, an amino group, or an alkyl substituted amino group, while the second auxochrome is a hydroxyl group, an amino group, an alkyl substituted amino group or ##STR2## where X' is a hydrogen atom, an alkyl group, an amino group, a substituted amino group or an alkoxyl group.

Abstract: A process for manufacturing a thin-film magnetic bubble domain detection device in which first a spacer and then a conductor film are deposited onto a substrate, and then the conductor film is removed from a predetermined region using a mask. Thereafter a magnetic field sensing film is deposited onto the substrate, with the mask still thereon, and then the mask is removed.

Abstract: A thin-film bubble domain detection device for use in a magnetic bubble memory comprises two metallic conductor leads formed with sloped opposing edges on the SiO.sub.2 spacer layer of a garnet substrate and a permalloy magnetoresistive sensing element formed therebetween. A method for making the device uses a first photoresist mask in ion milling in a conductor layer to expose an area of spacer, followed by deposit of a permalloy film over the substrate and onto the exposed spacer before removal of the first mask. Extraneous permalloy is lifted off when the first photoresist is removed. A second mask is used to simultaneously ion mill the final conductor lead and sensing element configurations. In one embodiment, first and second dielectric layers are added to the device to improve bubble propagation and provide an easily planned product.