Measurement device

A measurement deice comprising:

• a light source section configured to couple a plurality of laser beams having different wavelengths and to emit measuring light;
• an illuminating section configured to illuminate a measurement target with the measuring light at a predetermined illuminating angle;
• a light receiving section configured to receive reflected measuring light from the measurement target;
• and
• a controlling section configured to compute a reflectance at each of the wavelengths, based on a light receiving result;
• wherein the light source section includes:
• a first light source configured to emit a laser beam having a first wavelength;
• a second light source configured to emit a laser beam having a second wavelength different from a wavelength of the first light source;
• and
• a dichroic mirror disposed in a position in which optical axes of laser beams having two wavelengths intersect, the dichroic mirror being configured to transmit one of the laser beams and reflect the other of the laser beams and to combine the laser beams having the two wavelengths,
• the light receiving section includes:
• a first light receiving unit configured to receive the reflected measuring light from a short distance;
• a second light receiving unit configured to receive the reflected measuring light from a medium distance;
• and
• a third light receiving unit configured to receive the reflected measuring light from a long distance, and
• the controlling section is configured to select which of light receiving results from the first light receiving unit, the second light receiving unit, and the third light receiving unit to use, based on a distance to the measurement target.