Abstract: An electronic camera having a printer with a portable printing function and a sheet feed device suitable for use with the printer. The electronic camera includes an image storage device it photoelectrically convert an optical image to picture data, a first memory to store picture data, and a printer unit to print the picture data. The printed picture data may be fed by a sheet drive mechanism having vibration member and a piezoelectric element fixed to the vibration member and expanding and contracting according to an applied voltage, and a driver which applies to the piezoelectric element a voltage including an alternating component, and at least one projection formed on the vibration member in a position in the neighborhood of a peak of the standing wave, and a sheet separation unit formed on the vibration member, outside the range of the standing wave.

Abstract: An electronic camera having a printer with a portable printing function and a sheet feed device suitable for use with the printer. The electronic camera includes an image storage device it photoelectrically convert an optical image to picture data, a first memory to store picture data, and a printer unit to print the picture data. The printed picture data may be fed by a sheet drive mechanism having vibration member and a piezoelectric element fixed to the vibration member and expanding and contracting according to an applied voltage, and a driver which applies to the piezoelectric element a voltage including an alternating component, and at least one projection formed on the vibration member in a position in the neighborhood of a peak of the standing wave, and a sheet separation unit formed on the vibration member, outside the range of the standing wave.

Abstract: An electronic camera having a printer with a portable printing function and a sheet feed device suitable for use with the printer. The electronic camera includes an image storage device it photoelectrically convert an optical image to picture data, a first memory to store picture data, and a printer unit to print the picture data. The printed picture data may be fed by a sheet drive mechanism having vibration member and a piezoelectric element fixed to the vibration member and expanding and contracting according to an applied voltage, and a driver which applies to the piezoelectric element a voltage including an alternating component, and at least one projection formed on the vibration member in a position in the neighborhood of a peak of the standing wave, and a sheet separation unit formed on the vibration member, outside the range of the standing wave.

Abstract: A method of treating water with ozone comprising:(1) generating ozone from oxygen by an ozone generator,(2) supplying the resulting ozone-containing gas to at least three silica gel-packed adsorption towers one after another to cause the silica gel to adsorb ozone selectively from the gas while recycling discharged gas from the adsorption tower to the ozone generator, the adsorption tower being maintained at a temperature of -180.degree. to 10.degree. C, the silica gel containing a heavy metal in an amount of not greater than 1.