3.6CONTROLLING THE HEAD ACTIVATION (DST) PULSE WIDTH

3.6.1Calculation of the Head Activation Pulse Width

To execute high quality printing using the printer, the value that is calculated using the following equation (2) must be adjusted according to the printer installation environment. Calculate each value used according to the steps in Sections 3.6.2 to 3.6.5 and control so that the pulse width with the t (msec) value obtained by substituting each value into the equation (2).

Equation (2):

R

t = E⋅ V2 ⋅C⋅D

t:Heat pulse width (ms)

V:

Applied voltage (V)

 

E:

Standard applied energy (mj)

Refer to Section 3.6.2.

R:

Head resistance (Ω)

Refer to Section 3.6.3.

C:

Head activation pulse term coefficient

Refer to Section 3.6.4.

D:

Heat Storage coefficient

Refer to Section 3.6.5.

Printing using too high of voltage or too long of pulse width may shorten the life of the thermal head.

3.6.2Calculation of the Applied Energy

The applied energy should be according to the temperature of the thermal head and operational environment.

The thermal head has a built-in thermistor. Measure the temperature using the thermistor resistance. The applied energy also differs according to the thermal paper used.

The applied energy is calculated by substituting a temperature coefficient and thermal paper coefficient into the equation (3).

Equation (3):

E= E0 ⋅ P ⋅ (1−Tc (Tx−25))

E:

Print energy (mj)

 

 

E0: Standard applied energy

0.210 (mj)

 

TX: Detected temperature using the thermistor (°C) 1

 

P:

Thermal paper coefficient

 

 

 

TF50KS-E2C (Nippon Paper Industries):

0.9

 

PD160R-N (New Oji Paper Co., Ltd):

1.0

 

HP220AB1 (MITSUBISHI PAPER MILLS LIMITED):

1.0

TC: Temperature coefficient:

 

0.0076

∗1 The thermistor resistance value at TX (°C). Refer to Section 3.6.6.

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