OTELO is an ultradeep, 2D-spectroscopic (R$\sim$700) blind survey, defined on a window of 210 Å centred at 9175 Å targeting a region of the Extended Groth Field that is embedded in the Deep field 3 of the Canada-France-Hawaii Telescope Legacy Survey (CFHTLS). Is the deepest pointing of GALEX in imaging and spectroscopy. Such Pseudo-spectra(PS) were obtained using the red Tunable Filter (RTF) of the OSIRIS instrument at GTC. OTELO detects emission lines with a limiting flux of $5 \times 10^{-19}$ erg/s/cm and observed equivalent widths (EW)$\ge$5 Å. Besides, OTELO is targeting low mass galaxies, down to $M_{*}\sim 10^{6}{\rm M_{\odot}}$. As reference, the MUSE Hubble Ultra Deep Field barely reach down to $M_{*} \sim 10^{8} {\rm M_{\odot}}$ in few cases, and only at redshifts below 0.4, and none at redshifts above $\sim0.7$. However, OTELO detects the bulk of emitters around $10^{8}-10^{9} {\rm M_{\odot}}$ even at redshifts as high as 1.4, reaching down to $10^{7}{\rm M_{\odot}}$ at redshift 0.4. Then, OTELO reaches stellar masses one order of magnitude lower than MUSE Hubble Ultra Deep Field. We were able to generate a catalogue of 60[OII] emitters at $< z > = 1.43$. The 93% of those have masses in the range of $10^{8}<M_{*}/{\rm M_{\odot}}<10^{9}$, classified as late-type galaxies. From [OII] emitters we generated the Luminosity Function, sampling it down to $\sim 1$ dex lower than in previous works. Taking into account the results obtained for the lines ${\rm H_{\alpha}}$, ${\rm H_{\beta}}$ and [OII], we were able to study the star formation rate, star formation rate density, and number density and the evolution of those parameters between $z \sim 0.4$ and 1.43. We obtained a robust estimate of the specific star formation rate stellar mass relation based on the lowest mass sample published so far. We also determine a flat trend of the star formation rate density and number density with redshift.