Time Scan: Instrument Tab
F.2.1 Time Scan: Instrument Tab
Parameter Name
Setting Range
Data mode
%T, Abs, E(S), E(R), %R (U-1900: %T, Abs E(S) and E(R) alone) (U-5100: %T and Abs alone)
Wavelength
Input range
U-1900/2900/2910/
190.00 to
1100.00 nm U-4100/UH4150 175.00 to
3900/3900H/5100
3300.00 nm
Scan time
Input range
U-
60 to 99999 s
1900/2900/2910/5100 U-3900/3900H
60 to 99990 s
U-4100/UH4150
60 to 18400 s
High Resolution (with U-
On, Off
3900/3900H/4100/UH4150) Response (with
Fast, Medium, Slow
U-1900/2900/ 2910/5100)
Delay
0 to 3600 s
Auto Zero before each run
ON, OFF When turned ON (checked), auto zero
measurement (100%T set in transmittance mode, 0 Abs set in absorbance mode) is carried out by using the measuring wavelength before each measurement.
Lamp change mode (for
Auto, D2 only, WI only
other than U-5100) Lamp change wavelength
325.00 to 370.00 nm
(for other than U-5100)
WI Lamp (for other than
On, Off
U-5100) D2 lamp (for other than U-
On, Off
Parameter Name
Setting Range
Slit width (nm)
Model U-3900/3900H
Input range
U-1900
: Fixed at 4 nm U-2900/2910 : Fixed at 1.5 nm U-5100
: Fixed at 5 nm
U-4100
: Select a slit width in the ultraviolet/visible region. It is recommended to fix the slit width for ordinary measurement.
Auto : The slit width is automatically controlled according to the optical energy level under a specified photomultiplier voltage. Concretely, the slit width is widened at a low optical energy level and narrowed at a high optical energy level. In other words, this is a function depending mainly on the S/N ratio (signal-to-noise ratio). In this mode, the slit width automatically changes in a range of about 0.01 to 14 nm. This mode cannot be set simultaneously with PMT mode “Auto”.
Fixed : The slit width is selectable in a range of 0.1 to 8.0 nm in 0.01 (0.02) nm steps. (The parenthesized step corresponds to slit width 2.4 nm or wider.)
PMT mode (for
Auto, Fixed
U-3900/3900H/
When “Fixed” is selected, the photomultiplier voltage
4100/UH4150)
is settable.
PMT voltage (for
0 to 1000 V
U-3900/3900H/ 4100/UH4150)
Sampling interval
Refer to APPENDIX G.2.
(s) Path correct
ON, OFF When turned ON (checked), cell length correction is
effective.
Path Length
0.1 to 100.0 mm
Parameter Name
Setting Range
Attenuation (with
The beam attenuator is inserted on the reference
U-4100/UH4150)
side. Set the attenuation ratio of the attenuator. This setting is usable for a sample whose absorbance and transmittance/reflectance are 4 Abs or more and 0.1%T or less, respectively. For usage, select the Attenuation command from the Spectrophotometer menu after baseline measurement. Then, carry out sample measurement.
None 1/10 1/100
Detector change
A function for automatically correcting the difference
correct (with
in photometric value between the detector
U-4100/UH4150)
changeover points in the near infrared and visible regions.
On Off
Detector change
Set up a wavelength for changeover between the
wavelength (with
detectors for the ultraviolet/visible and near infrared
U-4100/UH4150)
regions. Input range: 700.0 to 900.0 nm
Scan speed (with
Set up a scan speed in the near infrared region.
U-4100/UH4150)
0.75 nm/min 7.5 37.5 75 150 300 750 1500 3000 6000
Parameter Name
Setting Range
Slit width (with
Set up a slit width in the near infrared region.
U-4100/UH4150)
Fixed : Input range: 0.1 to 20.0 nm, in steps of
0.1 nm
Auto : The slit width is automatically controlled according to the optical energy level. This function is intended to keep the S/N ratio (signal-to-noise ratio) constant in the measuring wavelength range as far as possible. In this mode, the slit width automatically changes in a range of about
0.1 to 36 nm. This mode cannot be set simultaneously with Light control mode “Auto”.
PbS Gain (with
Specify a sensitivity level of the detector for the near
U-4100/UH4150)
infrared region. The PbS sensitivity is settable at four levels. Level 1 is used as a reference. Levels 2, 3 and 4 are 2, 4 and 8 times as high as level 1, i.e., the sensitivity rises in the order of 1, 2, 4 and 8 (times). For high resolution measurement in the near infrared region, use a higher sensitivity (PbS sensitivity level 3 or 4). However, use of a high sensitivity inevitably entails an increase in noise level. Therefore, PbS sensitivity level 2 is generally recommended. Use Pbs sensitivity level 1 for measuring quite a flat spectrum with no large absorbance change or checking spectral features alone with minimum noise.
Light control mode
A mode for controlling the light quantity in the near
(with U-4100/
infrared region.
UH4150)
Fixed : Used for ordinary measurement. Auto : Used when measurement cannot be
performed with the slit width fixed because the light quantity in the near infrared region is excessive.