In this paper, a full analytical and exact expression form of turn-on time delay, t(on), of degraded bulk uncooled semiconductor laser diode (DBUSLD) has been presented in terms of nonradiative, A(nr), radiative, B-r, Auger recombination coefficients, C-auger, cavity dimensions, threshold carrier density, N-th,, injection current, I-inj, number of "0" bits preceding the considered bit, N-bit, bit-rate, Brate and temperature of operation, T. Also we included, in addition to the mentioned parameters, dark defect (DD) parameters, i. e. number of DD, n(DD) and width of DD, w(DD). In addition, an exact and full analytical expression form of carrier density, N, corresponding to the current flowing through laser active region, I, and in term of all the above mentioned parameters has been derived which can be used to determine any value of N corresponding to I exactly, therefore, the temperature dependence (TD) of threshold carrier density of DBUSLD (which is used in ton calculation) is calculated corresponding TD of threshold current of the device. Simulation results show that worst case of DBUSLD is when operates with large n(DD) and at high temperature degree.