Provided is an optical article having a substrate, a primer layer generated by curing a polymerizable composition for forming the primer layer, and a photochromic layer containing a photochromic compound in this order, in which the polymerizable composition for forming the primer layer contains a component A: a polyisocyanate, a component B: a hydroxy group-containing polymerizable compound, and a component C: a polymerizable compound having a viscosity of 100 cP or less and being selected from the group consisting of (meth)acrylates and vinyl ethers.

Provided is an article which transitions from a first state to a second state in response to actinic radiation. The article includes an indolenaphthopyran, wherein in the first state the article exhibits a percent transmission of greater than 80 percent, and in the second state the article exhibits a percent transmission of between 35 and 75 percent, and a TSB value of less than 20 percent. The article can be a photochromic article selected from ophthalmic articles, display articles, windows, mirrors, active liquid crystal cell articles, and passive liquid crystal cell articles.

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.

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.

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.

A photochromic compound including a core skeletal structure represented by the following Formula (I),

##STR00001## wherein D is oxygen or sulfur; E is oxygen, sulfur, or NR.sup.2′; a is 0 or 1; R.sup.1 is hydrogen, or substituted or unsubstituted alkyl; R.sup.2 and R.sup.2′ are each independently selected from hydrogen, substituted or unsubstituted alkyl, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, or substituted or unsubstituted heterocycloalkyl; and the photochromic compound is a thermally reversible photochromic compound.

A photochromic compound including a core skeletal structure represented by the following Formula (I),

##STR00001## wherein D is oxygen or sulfur; E is oxygen, sulfur, or NR.sup.2′; a is 0 or 1; R.sup.1 is hydrogen, or substituted or unsubstituted alkyl; R.sup.2 and R.sup.2′ are each independently selected from hydrogen, substituted or unsubstituted alkyl, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, or substituted or unsubstituted heterocycloalkyl; and the photochromic compound is a thermally reversible photochromic compound.

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.

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.