Detecting apparatus for detecting a tracking error signal in an optical information recording and/or reproducing apparatus and an optical information recording and/or reproducing apparatus

A detecting apparatus for detecting a tracking error signal in an optical information recording and/or reproducing apparatus, comprising:

• spot forming means for forming three spots of a main spot, a first subspot, and a second subspot on an optical information recording medium;
• light-receiving means for receiving reflected light from the three spots of said main spot, said first subspot, and said second subspot, said light-receiving means having light-receiving elements corresponding to the respective spots;
• first detecting means for detecting a tracking error signal, using an output from the light-receiving element corresponding to said main spot or using outputs from the light-receiving elements corresponding to the three spots of said main spot, said first subspot, and said second subspot, if there is a tracking guide groove in said optical information recording medium;
• second detecting means for detecting a tracking error signal, using an output from the light-receiving element corresponding to said first subspot and an output from the light-receiving element corresponding to said second subspot, if there is no tracking guide groove in said optical information recording medium;
• determining means for determining whether there is a tracking guide groove in said optical information recording medium;
• and
• changing means for changing the separation in a direction perpendicular to the track direction between the center of said main spot and the center of said first subspot or said second subspot on said optical information recording medium, based on a result of determination by said determining means, wherein said changing means changes the separation in the direction perpendicular to the track direction between the center of said main spot and the center of said first subspot or said second subspot on said optical information recording medium to about 0.4 .mu.m if there is no tracking guide groove in said optical information recording medium and changes the separation in the direction perpendicular to the track direction between the center of said main spot and the center of said first subspot or said second subspot on said optical information recording medium to an arbitrary value between 0.55 .mu.m and 0.8 .mu.m if there is a tracking guide groove in said optical information recording medium.

An optical information recording and/or reproducing apparatus comprising:

• spot forming means for forming three spots of a main spot, a first subspot, and a second subspot on an optical information recording medium in order to perform recording and/or reproduction of information;
• light-receiving means for receiving reflected light from the three spots of said main spot, said first subspot, and said second subspot, said light-receiving means having light-receiving elements corresponding to the respective spots;
• determining means for determining whether there is a tracking guide groove in said optical information recording medium;
• changing means for changing a separation in a direction perpendicular to a track direction between the center of said main spot and the center of said second subspot on said optical information recording medium, based on a result of a determination by said determining means, wherein said changing means changes the separation in the direction perpendicular to the track direction between the center of said main spot and the center of said second subspot on said optical information recording medium to about 0.4 .mu.m if there is no tracking guide groove in said optical information recording medium and changes the separation in the direction perpendicular to the track direction between the center of said main spot and the center of said second subspot on said optical information recording medium to an arbitrary value between 0.55 .mu.m and 0.8 .mu.m if there is a tracking guide groove in said optical information recording medium.