Imaging lidar systems and K-meters employing tunable and fixed frequency laser transmitters

An apparatus for detecting and imaging a volume in water, the volume being at a selected water depth and the selected water depth having a selected Jerlov Class associated therewith, including:

• means for tuning or setting the operating wavelength of a laser transmitter to a selected wavelength which optimizes performance of said laser transmitter with respect to said selected Jerlov Class;
• means for generating short pulses of light from said laser transmitter;
• means for projecting said generated short pulses of light toward the water and at said volume in said water;
• means for detecting said pulses of light reflected back from said volume using gated detector means;
• and
• means for converting said detected pulses of light to a video image of said volume.

An apparatus for detecting and imaging a volume in water, the volume being at a selected water depth including:

• means for tuning or setting the operating wavelength of a laser transmitter to a selected wavelength;
• means for generating short pulses of light from said laser transmitter;
• means for projecting said generated short pulses of light toward the water and at said volume in said water;
• means for detecting said pulses of light reflected back from said volume using gated detector means;
• and
• means for converting said detected pulses of light to a video image of said volume.

A method of measuring the diffuse attenuation coefficient or K-factor in water including the steps of:

• tuning or setting the selected operating wavelength of a laser so as to optimize performance of said laser with respect to the depth of water;
• selectively generating short pulses of light using said laser water;
• projecting said short pulses of light toward the water;
• detecting said pulses of light reflecting back from said water after a time delay corresponding to round-trip propagation time of said light pulses to and from said water;
• and
• converting said detected pulses of light to determine K-factor.

An apparatus of measuring the diffuse attenuation coefficient or K-factor in water including:

• means for tuning or setting the selected operating wavelength of a laser so as to optimize performance of said laser with respect to the depth of water;
• means for selectively generating short pulses of light using said laser water;
• means for projecting said short pulses of light toward the water;
• means for detecting said pulses of light reflecting back from said water after a time delay corresponding to round-trip propagation time of said light pulses to and from said water;
• and
• means for converting said detected pulses of light to determine K-factor.