A sealed encoder module for mounting onto a machine so as to measure relative displacement of first and second parts of the machine. The sealed encoder module can comprise, a scale, a readhead comprising a scale signal receiver, and an integral protective housing which encapsulates at least the scale and said scale signal receiver. The sealed encoder module can be configured to determine and output diagnostic information regarding a scale signal detected by the readhead.

A holding mechanism used in a measuring device includes a first groove, a second groove, and a pair of holding members holding the detection device by being attached to first and second sides in a length direction of a scale frame. The pair of holding member include a plate-like main body, a first hook portion engaging with the first groove, a second hook portion engaging with the second groove, and a projecting tab projecting from the main body and positioned at a gap. The pair of holding members are displaced from first and second sides toward the detection device along the length direction of the scale frame and the projecting tab is inserted into the gap, and thereby the projecting tab biases the scale frame and the detection device in mutually separating directions.

There is provided a displacement measuring apparatus capable of being used in a vacuum environment. The displacement measuring apparatus includes a scale and a detection head part disposed in such a manner as to be relatively displaceable to the scale and as to face the scale with a predetermined gap. The detection head part detects a displacement or position relative to the scale. The scale is disposed in a vacuum. The detection head part is housed in a housing holder separating an atmospheric environment side from a vacuum environment side. In a gap between the detection head part and the scale, the housing holder includes a relay means for passing a detection signal between the detection head part and the scale,

A sealed encoder module for mounting onto a machine so as to measure relative displacement of first and second parts of the machine. The sealed encoder module can comprise, a scale, a readhead comprising a scale signal receiver, and an integral protective housing which encapsulates at least the scale and said scale signal receiver. The sealed encoder module can be configured to determine and output diagnostic information regarding a scale signal detected by the readhead.

An encoder apparatus comprising a scale and a readhead assembly comprising a scale signal receiver. The scale and the scale signal receiver are located within a protective housing which is configured to protect them from contamination located outside the protective housing and comprises a seal through which the scale signal receiver can be connected to a part outside the protective housing. The arrangement of the scale signal receiver inside the protective housing is independent of the scale and protective housing.

A sealed encoder module for mounting onto a machine so as to measure relative displacement of first and second parts of the machine. The sealed encoder module can comprise, a scale, a readhead comprising a scale signal receiver, and an integral protective housing which encapsulates at least the scale and said scale signal receiver. The sealed encoder module can be configured to determine and output diagnostic information regarding a scale signal detected by the readhead.

An encoder apparatus comprising a scale and a readhead assembly comprising a scale signal receiver. The scale and the scale signal receiver are located within a protective housing which is configured to protect them from contamination located outside the protective housing and comprises a seal through which the scale signal receiver can be connected to a part outside the protective housing. The arrangement of the scale signal receiver inside the protective housing is independent of the scale and protective housing.

Disclosed is an optical coherence tomography scanner and a method for recording sub-surface scans of an object, wherein a position encoder is arranged in the path of the probing beam of an interferometric system. The encoder pattern is detected in a sequence of A scans at generated for different probing beam positions on the scanned object, the probing beam position and/or inclination for at least one A scan of said sequence of A scans is deducing based on the detected encoder pattern, and the sub-surface scan of the object is generated based on the sequence of A scans taking into account the deduced probing beam position and/or inclination.

A linear encoder includes a scale disposed within a housing and a scanning unit that is displaceable in a measuring direction relative to the scale. The scanning unit includes a scanning head disposed inside of the housing opposite to the scale such that the scale is scannable by the scanning head, as well as a mount to which the scanning head is fastened, and a driving component, via which the mount is coupled to a mounting base disposed outside of the housing. A vibration damper suppresses vibrations transversely to the measuring direction. The vibration damper is disposed on the mount or on the scanning head, and includes a damping mass and an elastic element. The damping mass is fastened by the elastic element to an attachment surface of the mount or of the scanning head.

Disclosed is an optical coherence tomography scanner and a method for recording sub-surface scans of an object, wherein a position encoder is arranged in the path of the probing beam of an interferometric system. The encoder pattern is detected in a sequence of A scans at generated for different probing beam positions on the scanned object, the probing beam position and/or inclination for at least one A scan of said sequence of A scans is deducing based on the detected encoder pattern, and the sub-surface scan of the object is generated based on the sequence of A scans taking into account the deduced probing beam position and/or inclination.