Electrochromic element, optical filter, lens unit, imaging device, and window component

A lens unit comprising:

• an imaging optical system including a plurality of lenses;
• and
• an optical filter comprising an electrochromic element and an active element connected to the electrochromic element,
• wherein the electrochromic element comprises:
• a pair of electrodes;
• and
• an electrochromic layer disposed between the pair of electrodes, the electrochromic layer containing an electrochromic material, a solvent, and a cyanoethylated polymer,
• wherein the proportion of the cyanoethylated polymer to the solvent is 20% by weight to less than 40% by weight, and
• wherein the optical density of the electrochromic layer has a temperature coefficient of −0.2%/° C. to less than +0.2%/° C. at a temperature from room temperature to 80° C.

An imaging device comprising:

• an imaging optical system including a plurality of lenses;
• an electrochromic element;
• and
• an imaging element configured to receive light after passing through the electrochromic element,
• wherein the electrochromic element comprises:
• a pair of electrodes;
• and
• an electrochromic layer disposed between the pair of electrodes, the electrochromic layer containing an electrochromic material, a solvent, and a cyanoethylated polymer,
• wherein the proportion of the cyanoethylated polymer to the solvent is 20% by weight to less than 40% by weight, and
• wherein the optical density of the electrochromic layer has a temperature coefficient of −0.2%/° C. to less than +0.2%/° C. at a temperature from room temperature to 80° C.

An imaging device to which a lens unit having an imaging optical system including a plurality of lenses is removably mounted, the imaging device comprising:

• an electrochromic element;
• and
• an imaging element configured to receive light after passing through the electrochromic element,
• wherein the electrochromic element comprises:
• a pair of electrodes;
• and
• an electrochromic layer disposed between the pair of electrodes, the electrochromic layer containing an electrochromic material, a solvent, and a cyanoethylated polymer,
• wherein the proportion of the cyanoethylated polymer to the solvent is 20% by weight to less than 40% by weight, and
• wherein the optical density of the electrochromic layer has a temperature coefficient of −0.2%/° C. to less than +0.2%/° C. at a temperature from room temperature to 80° C.

A window component comprising:

• a pair of transparent substrates;
• an electrochromic element disposed between the pair of transparent substrates;
• and
• an active element connected to the electrochromic element,
• wherein the electrochromic element comprises:
• a pair of electrodes;
• and
• an electrochromic layer disposed between the pair of electrodes, the electrochromic layer containing an electrochromic material, a solvent, and a cyanoethylated polymer,
• wherein the electrochromic element controls the amount of light passing through the pair of transparent substrates, and
• wherein the proportion of the cyanoethylated polymer to the solvent is 20% by weight to less than 40% by weight, and
• wherein the optical density of the electrochromic layer has a temperature coefficient of −0.2%/° C. to less than +0.2%/° C. at a temperature from room temperature to 80° C.

An electrochromic element comprising:

• a pair of electrodes;
• and
• an electrochromic layer containing an electrochromic material,
• wherein the optical density of the electrochromic layer has a temperature coefficient of −0.2%/° C. to less than +0.2%/° C. at a temperature from room temperature to 80° C.