Rear glass

A rear glass for attachment to a lift-up backdoor that closes an opening in a rear portion of a vehicle, the rear glass comprising:

• a glass plate;
• a defogger disposed in a vicinity of a center of the glass plate in an up-down direction;
• and
• a shared antenna installed on the glass plate upward or downward of the defogger, wherein the shared antenna includes:
• a power supply unit;
• an AM antenna connected to the power supply unit;
• and
• an FM antenna connected to the power supply unit,
• wherein the FM antenna includes:
• a rectangular frame-shaped FM main body element that is coupled to the power supply,
• a first FM antenna element extending toward the defogger from the power supply unit;
• and
• a second FM antenna element coupled to an end portion of the first FM antenna element and extending in the horizontal direction, wherein the second FM antenna element is positioned closer to the defogger than is the AM antenna, and is capacitively coupled to the defogger, and
• wherein the first FM antenna element and the FM main body element are respectively directly connected to the power supply unit, and the FM main body element is not directly connected to the first and second FM antenna elements,
• wherein the length of the defogger in the up-down direction is 65 to 85% of the length of the rear glass in the up-down direction, and
• a relationship between an element length LAM of the AM antenna, a center wavelength λFM-C corresponding to a reception frequency band of the FM antenna and a wavelength shortening coefficient α of the glass plate satisfies 0.49×α×λFM-C≤LAM≤0.67×α×λFM-C.