Automatic focus adjusting device

An automatic focus adjusting device comprising

• (a) a lens setting means capable of setting a lens to a particular position;
• (b) a range finding means capable of generating a signal corresponding to a distance from said device to an object to be photographed;
• (c) a primary judging means which determines whether or not a diaphragm setting is within a range in which fixed focus photography is possible;
• and
• (d) a secondary judging means which determines whether or not said signal from said range finding means is capable of correctly operating said lens setting means to position said lens at a point corresponding to said distance to said object;
• wherein said secondary judging means operates only when said primary judging means determines that said diaphragm setting is not within said range in which fixed focus photography is possible and said lens setting means is operated only when said secondary judging means determines the output signal is at a level capable of correctly operating said lens setting means.

An automatic focus adjusting method comprising

• (a) a first step of judging whether or not a diaphragm setting is within a range in which fixed focus photography is possible;
• (b) a second step of judging whether or not an output of a range finding means is at a level capable of operating a lens setting means to position a lens at a point corresponding to a distance between said range finding means and an object;
• (c) a third step of operating said lens setting means;
• and
• (d) a fourth step of setting said lens to a point corresponding to said output of said range finding means;
• wherein said fourth step is performed only when said diaphragm setting is deemed, in said first step, not within the range in which fixed focus photography is possible and only when said output of said range finding means is deemed capable of correctly operating said lens setting means to set said lens at a position corresponding to a distance between said range finder and said object.