Provided is an envelope which includes: a first substrate; a second
substrate opposed to the first substrate; a frame interposed between the
first substrate and the second substrate; and a low melting point metal
for bonding the first substrate and the frame to each other. In
particular, in such a configuration, the substrate or the frame has a
first region and a second region which are brought into contact with the
low melting point metal, and in the first region, a material capable of
higher maintaining airtightness with the low melting point metal than the
second region is in contact with the low melting point metal, while in
the second region, a material having a stronger binding power on the low
melting point metal than the first region is in contact with the low
melting point metal.