Provided is a method and an apparatus for indicating minimum exposure of a surface to UVC light emitted by a source during a decontamination process to achieve a desired level of pathogen reduction. The apparatus includes a photochromic material to be applied to, or applied adjacent to the surface. The photochromic material is to exhibit a visible response to receiving the minimum exposure to the UVC light, and exhibit the visible response to a lesser extent after the photochromic material ceases to be exposed to the UVC light emitted by the source. A protective layer of material that is substantially transparent to the UVC light emitted by the source is positioned over the photochromic material to be disposed between the source and the photochromic material during the decontamination process.

Implantable corneal and intraocular implants such as a mask are provided. The mask can improve the vision of a patient, such as by being configured to increase the depth of focus of an eye of a patient. The mask can include an aperture configured to transmit along an optical axis substantially all visible incident light. The mask can further include a transition portion that surrounds at least a portion of the aperture. This portion can be configured to switch from one level of opacity to another level of opacity through the use of a controllably variable absorbance feature such as a switchable photochromic chromophore within a polymer matrix.

Provided are a photochromic compound represented by General Formula 1, and the like. In General Formula 1, R.sup.100 to R.sup.111, and X.sup.1 and X.sup.2 each independently represent a hydrogen atom or a substituent, and two or more substituents may be bonded to form a ring structure.

##STR00001##

Provided is an oriented polymeric sheet comprising a photochromic-dichroic material, wherein the sheet exhibits dichroism in an activated state. Also provided is a multilayer composite comprising at least a support layer; and an oriented thermoplastic polymeric sheet having two opposing surfaces and comprising a photochromic-dichroic material. The sheet exhibits dichroism in an activated state. At least one surface of the sheet is connected to at least a portion of the support layer. The present invention also relates to an optical element comprising the multilayer composite. Related methods also are disclosed.

A matrix processing apparatus having a three-dimensional slice access memory and an input-/output block. The slice access memory includes cells organized into cell slices, each slice storing an entire selected data matrix. The three-dimensional slice access memory is configured to allow read/write access to the entire data matrix at the same time. The input/output block is connected to the three-dimensional slice access memory and is configured to format data into a format acceptable to the three-dimensional slice access memory.

Implantable corneal and intraocular implants such as a mask are provided. The mask can improve the vision of a patient, such as by being configured to increase the depth of focus of an eye of a patient. The mask can include an aperture configured to transmit along an optical axis substantially all visible incident light. The mask can further include a transition portion that surrounds at least a portion of the aperture. This portion can be configured to switch from one level of opacity to another level of opacity through the use of a controllably variable absorbance feature such as a switchable photochromic chromophore within a polymer matrix.

Provided is a method and an apparatus for indicating minimum exposure of a surface to UVC light emitted by a source during a decontamination process to achieve a desired level of pathogen reduction. The apparatus includes a photochromic material to be applied to, or applied adjacent to the surface. The photochromic material is to exhibit a visible response to receiving the minimum exposure to the UVC light, and exhibit the visible response to a lesser extent after the photochromic material ceases to be exposed to the UVC light emitted by the source. A protective layer of material that is substantially transparent to the UVC light emitted by the source is positioned over the photochromic material to be disposed between the source and the photochromic material during the decontamination process.

A multilayer photochromic article can include a photochromic substrate, which may include a first photochromic layer defining a surface of the substrate, and a second photochromic layer positioned between the surface of the photochromic substrate and a source of actinic radiation, and in which the photochromic substrate and the second photochromic layer are selected such that the fade half-life of the photochromic substrate or the half-life of the first photochromic layer defining the surface of the substrate are greater than the fade half-life of the second photochromic layer.

A composition includes an isomerized polymer containing a structural unit containing an isomerized structure and an isomerized low molecular weight compound, the composition being fluidized by light irradiation from a solid state and being reversibly non-fluidized.

Photochromic polyurethane laminates and methods for the formation of same wherein a photochromic polyurethane layer of the laminate is interposed between two primer coated transparent resin sheets.