Distance measuring device and distance measuring method
A distance measuring device includes a laser light source, an irradiation optical system comprising a beam spreader which is configured to spread the laser light about a first optical axis, a light reception optical system having a second optical axis different from the first optical axis and positioned to receive reflected light of the laser light from the object for measuring a distance to the object, a sensor with light receiving elements arranged in a first direction, the sensor being positioned to receive light reflected from the object which has passed through the light reception optical system, and a distance measuring unit configured to acquire distance information relating to the object based on the difference in time between emission of the laser light source and the reception of the reflected light at each of the plurality of light receiving elements.
1. A distance measuring device, comprising:
a laser light source configured to emit laser light;
an irradiation optical system configured to receive laser light from the laser light source and direct the laser light towards an object, the distance to which is to be measured, along a first optical axis, the irradiation optical system comprising a beam spreader configured to spread the laser light in a first direction crossing the first optical axis;
a light reception optical system having a second optical axis that is different from the first optical axis, the light reception optical system positioned to receive laser light reflected from the object;
a sensor comprising a plurality of light receiving elements arranged in a first sensor row paralleling the first direction and a second sensor row, which is parallel and adjacent to the first sensor row, the first sensor row comprising light receiving elements of a first sensitivity arranged adjacently along the first direction, the second sensor row comprising light receiving elements of a second sensitivity, different from the first sensitivity, arranged adjacently along the first direction, the sensor positioned to receive the light that has passed through the light reception optical system then reflected off the object; and
a distance measuring unit configured to acquire distance information for the object based on the difference in time between emission of the laser light source and the reception of the reflected light from the object at different light receiving elements of the plurality of light receiving elements.
2. The distance measuring device according to claim 1 , further comprising:
a rotation unit that rotates the laser light source, the irradiation optical system, the sensor, and the light reception optical system about a rotation axis which is parallel to the first direction.
3. The distance measuring device according to claim 2 , wherein at least a part of an irradiation surface of the irradiation optical system is disposed within a light reception range of the light reception optical system from the object.
4. The distance measuring device according to claim 2 , wherein the optical axis of the irradiation optical system and the optical axis of the light reception optical system are parallel to each other, and each of the optical axes intersects with the rotation axis.
5. The distance measuring device according to claim 2 , wherein the optical axis of the irradiation optical system and the optical axis of the light reception optical system are parallel to each other and are spaced from one another in a direction that is perpendicular to the rotation axis.
6. The distance measuring device of claim 2 , further comprising a mirror comprising a reflecting surface, the reflecting surface inclined at an angle to the rotation axis.
7. A distance measuring device for measuring the distance to an object, comprising:
a light beam emitter configured to emit a beam of light;
a beam spreader configured to direct the beam of light along a first optical axis towards a distant object and spread the beam outwardly in a first direction away from the first optical axis, wherein a width of the beam in the first direction increases as distance from the beam spreader increases; and
a light detector having a second optical axis, the first and second optical axes being parallel to each other, but not coaxial to each other, wherein
the light detector comprises a first sensor row paralleling the first direction and a second sensor row parallel to the first sensor row, the first sensor row comprising light detection elements of a first sensitivity arranged adjacently along the first direction, the second sensor row comprising light detection elements of a second sensitivity, different from the first sensitivity, arranged adjacently along the first direction.
8. The distance measuring device according to claim 7 , wherein light beam emitter, the beam spreader, and the light detector are inside a housing, and the housing is rotatable about a rotation axis.
9. The distance measuring device according to claim 8 , wherein the first and second optical axes are orthogonal to the axis of rotation.
10. The distance measuring device according to claim 8 , wherein the first and second optical axes intersect the axis of rotation.