Spectroscopic studies to develop laser ionization schemes suitable for titanium:sapphire (Ti:Sa) lasers were carried out in Tm. While efficient ionization schemes exist for dye laser based RILIS, development is needed for Ti:Sa laser based RILIS. The spectroscopic studies were performed at TRIUMF’s off-line laser ion source test stand with a system of tunable Ti:Sa lasers with the focus on developing simple, two-step resonant laser ionization schemes utilizing auto-ionizing (AI) states. Three different two-step resonance ionization schemes were developed using strong AI resonances which were determined with a measurement accuracy of about ±0.05 cm-1. The resulting laser ionization schemes for Tm are well suited for Ti:Sa laser based RILIS and will be used for on-line yield measurements in August 2018.